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DNS settings hijacked and av.exe won’t go away. Internet turns Inertnet!

by Greg on Feb.25, 2010, under Antivirus, Networking, Windows XP

Had a fun time today cleaning off some trojans and rootkits.  On this one client system, while trying to go online, the Internet  turned into the Inertnet! (Hahahha! I love that one!)  As usual, I have lots of ideas why, but no real evidence and clients saying “I don’t know how it got there.”  Doesn’t really matter though, it’s there and I am going to clean it off.  I managed to easily scan for and clean off a couple of them, but one would’t detect with any scanner.  AV.exe kept popping up, showing the fake windows security center and Antivirus 2010.  I used Process Explorer to see the offender, but I couldn’t find the file, it was hidden.

I rebooted with UBCD4Win, found the file and deleted it.  Problem is, this caused a mess in Windows. Nothing would load, I always got a “Open With” dialog box.  After some Googling, I found out where to fix that in HKCR in the registry.  In there, there was a setting for .exe files to open, and it was set to use av.exe in the user profile to open them!  How do you like that?!!

I wasn’t able to fix that in the current user profile, it was locked down somehow.  Opening in the Administrator account of XP allowed me to fix it though.  The default value for “exefile” should be set to:

“%1″ %*

(Just google that for more info.)

Ok, so got that all fixed.  Fun how you clean off these bugs, only to leave windows all messed up after!  Next, did all my final scans, tweaks and other items. (lock down IE, disable scripts/Flash/Adobe, add a windows update to Trusted Sites, and force user to use Firefox.  I also changed the icon on Firefox to the one for IE so the user will pretty much always use it!)  Then I tried to get all the updates caught up, only no go!  Wait, I am on the same Internet connection as my system, and it works for me, why not the client system?  Hmm… well they are on an isolated subnet, going through the firewall separately. (keeps their bugs off my systems!)  But, wait, those are the same DNS settings?

AH! Take a look at those NIC properties in XP.  DNS is hard set to 93.188.x.x!  Nslookup shows that as some place at a .com.ua domain. Well, let’s fix that one, and set to DHCP like it should be!  Problem solved, Windows Update works!

Fun stuff!  I’ve cleaned a lot of bugs over the years, and I’ve heard of DNS hijacking, but that’s the first one I’ve seen like that.

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Rootkit from fes.sk/files

by Greg on Feb.09, 2010, under Antivirus, Internet, Networking, PC Repair, Security, Windows XP

I had a client recently that had their browsers hijacked. Everything they typed in the browser ended up redirecting them to some test_s.php file at “www.fes.sk”.  (Don’t open that, or you might end up with a virus!  I just wanted people to find this in case it might help clean this bug off!)

Not sure what this virus was, but it disable Microsoft Security Essentials and blocked even MalwareBytes and SuperAntispyware from detecting it.  I couldn’t find it and I was almost to the point of just reloading the computer because in this case it would have been faster to just copy the docs of and reload Windows XP.

I thought, let’s search that URL?  This was key, because it brought up some forum posts and someone mentioned HitMan PRO.  www.surfright.nl/en/hitmanpro

Never heard of this program, but thought since it had a 30 day trial I’d give it a quick shot.  I was very impressed, it scanned in litterally a few minutes. (like 2 or 3!)  It found a “Rootkit”, nothing more than that though, in a file called “ipsec.sys” in the system32/drivers directory.  Then it said, “Reboot to clean.” 

My client was very pleased to see it reboot, do another very quick scan, and he was able to browse the web again.

Hitman Pro was free for 30 days, but you had to activate it.  I believe it has a subscription price of just under $30/year for 3 PC’s. (as of 02/09/2010)  That’s not too bad I think.  Keep in mind though, this looks like a “remover” , not a real-time antivirus protection program.  You’ll still want Norton, NOD32, MSSE, whatever you like, for that.

Now, I have to ask… because all my clients are starting to ask… why do they need this when they already have MSSE, Norton, etc?  Why doesn’t the AV real-time protection actually protect them in the first place?  Well, I can’t answer that one.  But it drives me nuts, and it make it worthless to pay for a subscription to Norton or McAfee (or any other) when all they do is get subverted and taken down, even if it’s the clients fault.  Because of this I will only suggest a free product for now, at least until I start seeing the “for pay” products doing what they were paid to do.  And if I see a Rootkit or Trojan that I can’t easily clean off, I’ll recommend HitmanPro for now.  If that can quickly remove bugs for my clients every time I use it, I’ll tell them (my clients) to use it and even purchase it as a quick cleaning tool in addition to MSSE.

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The specified server cannot perform the requested operation

by Greg on Jan.12, 2010, under Networking, Windows 7, Windows Server

I was not able to access a newly joined Windows 7 computer on our domain from our Windows 2000 Server.  I just received that error.  “Cannot perform the requested operation”  Sharing was setup ok, permissions and security set ok, firewall was turned off.  I saw an Event ID 2017 on the Windows 7 system, too. Something about “unable to allocate from the system nonpaged pool”.

I found this online. Add the MaxNonpagedMemoryUsage value below in the client’s registry. (Windows 7 system)  Make a restore point first so you can undo if any problems arise.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters\MaxNonpagedMemoryUsage

 

DWORD VALUE: 0xFFFFFFFF

Next, restart the “Server” service on the Windows 7 machine.  Then go back to Windows 2000 Server and try to connect to \\window7machine and see if it can access it now.

This worked great for me, hopefully it works for you too.  However, it may be wise to increase that value in small increments from the default, which I THINK is 0×100000.   I just maxed it out and on my client system to test, and it’s working fine.  Just thought I’d make note of it.  If you have further problems, or this doesn’t fix the issue, remove the value and reboot.  This should return it back to the default.

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Exchange 2007 Server Powershell tests

by Greg on Jan.04, 2010, under Exchange Server, Networking

Get the test commands available:

get-help test*

Should list out the tests available to you.

 

Test overall system health:

test-systemhealth

 

Check Outlook Web services:

test-outlookwebservices –identity:amailblox@organization.com | fl

 

(note the “fl” at the end, helps reading output, otherwise it will not wrap the lines)

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ZFS CIFS and ACL Inheritance

by Greg on Jul.24, 2009, under Networking, OpenSolaris, Security

This is just another one of those things that didn’t make any sense and only partially does now. At least NOW I know there is more at play here than the simple solutions in Samba using create mask and create directory mask. In Linux, that’s how I would get around the issues of Windows directory permissions running on a Linux SMB share.

Now, I am learning to do things the OpenSolaris way. I am loving OpenSolaris and ZFS! However, coming from a Linux and Windows “way of life”, there are some differences that just aren’t clear. What kills me is, I try the RTFM thing, and somehow completely miss that one little thing that makes it all work. Off topic, but an example, coming from Linux, I would just type “su” and get root access. In OpenSolaris, that won’t work. Neither will “pfexec su”, nor “sudo su”. Then one day, after dealing with it for a week or so, I stumble upon a post where someone in an unrelated sample script typed “pfexec su – root”. There ya go! Argh!

Anyway, back on the ZFS/CIFS/ACL thing. It was driving me nuts that I couldn’t figure it out. I wanted a folder with this setup:
/pool/sharefs – owner:greg – group:domusers
greg and domusers should have full control and all folders under “sharefs” should inherit that.

So under linux/samba, that’s where I would do like “create mask = 770″ or simlar, and “force create group = domusers”. Something like that, can’t remember exactly. made it simple actually. It always wrote files with the right perms and ownership and other people in that group could read/write just fine.

Problem is, you can’t get very specific about who get’s what, where, and you can’t use more than one group. Well, sure enough, there’s a thing called “ACL” that handles that stuff now. It’s been around for a while now, but I never even heard of it until I started using OpenSolaris. I like how it seems to be more compatible with the way Windows handles ACL’s. What I don’t like is, it’s confusing. I get the NTFS/Share perms in Windows, been doing that a long time now. The CIFS/ZFS ACL thing kind of makes sense, and it will “click” at some point the more I use it.

After spending hours on this, I reached a point where I had to figure it out. Here’s what I did.

On the ZFS file system, create it normally for SMB access. Then I changed some properties for aclinherit and aclmode. Change those to “passthrough”:
zfs set -o aclinherit=passthrough -o aclmode=passthrough pool/sharefs

Then chmod/chown. OH! That’s another thing. You need to use /bin/chmod and /bin/ls! Not just type: chmod … That wont work. In OpenSolaris the default path points to /usr/gnu/bin/chmod, which doesn’t have the “A” or “V” options to set/view ACL’s. That was another thing that DROVE ME CRAZY!!! I read the man pages and manuals and docs online and I didn’t catch anything that said, “Hey, there are different versions of chmod and ls here!” I can’t believe the time wasting here! Back to the point, do this to put your own default perms on:

/bin/chmod 2774 /pool/sharefs
(I actually am not positive that is needed, but I think it set group as inheritable)

/bin/chmod -R A- /pool/sharefs
(that will wipe out the current perms)

/bin/chmod -R A=owner@:full_set:fd:allow /pool/sharefs
(resets perms with only that acl)

/bin/chmod -R A+group@:full_set:fd:allow /pool/sharefs
(that appends the group perms, full control)

/bin/chmod -R A+everyone@:read_set:fd:allow /pool/sharefs
(above appends everyone read access)

In all the above that will preset INHERITABLE permissions for the subdirectories.  Notice above there is one with “A=” on it?  That will reset the perms and set only that perm.  So I guess you may not even need the previous line for “A-” to reset.  (I am just learning here ya know!)

It looks as if that makes a little sense now.  You can view the current ACL’s like so:  ”/bin/ls -V /pool/sharefs”

In my case, I might want to add another user or group:

/bin/chmod -R A+user:stacy:full_set:fd:allow /pool/sharefs
/bin/chmod -R A+group:othergroup:full_set:fd:allow /pool/sharefs
/bin/chmod -R A+group:yetanothergroup:read_set:fd:allow /pool/sharefs

So with this setup I can now open the share on the server and create a file or folder with inherited permissions.  It does, however, save my username as a new owner, so keep that in mind.  But if the group stays in there with “domusers” as full read/write access, I am happy.

Well, now I get it just a little and it makes more sense compared to Windows ACL’s.  I didn’t go over any share specifics and authentication issues, this was just ACL’s!  I still have to RTFM my way around that for a while.  Next project, join OpenSolaris to a Windows domain.  (Which, BTW, does not work in NT Domain style connections, you have to use Active Directory.)

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Join Windows 7 to Samba PDC on Ubuntu Jaunty

by Greg on May.31, 2009, under Linux, Networking, Windows 7

I found some info on Google searches to get Windows 7 to join a Samba domain controller.  I have Ubuntu 9.04 Jaunty which runs Samba 3.3.2, which I guess does not work.  You need 3.3.4.   Windows 7 needs a registry change:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanWorkstation\Parameters]
“DomainCompatibilityMode”=dword:00000001
“DNSNameResolutionRequired”=dword:00000000

The above need to be added to allow the join to work.  Then find the key below and set those values to 0.

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Netlogon\Parameters]
“RequireSignOnSeal”=dword:00000000
“RequireStrongKey”=dword:00000000

The Netlogon values need to be updated, or Windows 7 will not allow domain logons.  You’ll get an error about credentials and no domain controller, or something like it.  Adding the second two will allow the logon.

Adding the registry keys above, plus upgrading Samba, did the trick.  I was able to join Windows 7 to Samba 3.3.4, but I did get a weird error about the DNS suffix being wrong.  I just said OK and left it.  I tried to change it several times after, too, but always get the same error.  System working fine so far though!

As for upgrading Samba, you’ll have to Google that one.  But here’s what I did, in a nutshell. (This is NOT a HOWTO, just a record of my experience, so if you follow this, it might break your system. Just be warned.  A Samba Server book might be nice for more information.)  I had a working domain controller, so I had a SAM database already with SID’s and passwords.  I didn’t want to lose those.  After backing up my server and Samba configs (including all the tdb files) I removed Samba 3.3.2 package from Ubuntu.  Then I downloaded the Samba source tar.gz for version 3.3.4, unpacked and “./configure” and then compiled. (make && make install)

At this point I found all my tdb files and copied them into the default Samba installation, which was different than the Ubuntu package.  I think the original tdb files from Ubuntu are in /var/lib/samba.  I copied all that to /usr/local/samba/var/lock. (the default when compiling from source)  I also setup a link from the original smb.conf in /etc/samba to /usr/local/samba/lib/smb.conf.

Now I’ve got my Windows 7 system logged in and joined to my Samba domain!

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Ubuntu rndc.key dynamic DNS updates failing

by Greg on May.12, 2009, under Internet, Linux, Networking

Just wanted to add a quick note about this as I couldn’t find a reason why dynamic DNS on my Ubuntu 9.04 system were failing. I had all the right perms, ownership, etc. I even opened up the files to full world writable and still, I got errors that the journal files could not be written to.

Log snippets:

error: journal open failed: unexpected error

jnl: create: permission denied

Learning as I go… there’s a thing in Ubuntu called Apparmor. Never even heard of this. This is what was keeping the files from being written to by the bind daemon.  I guess Apparmor has been in this for a while now, but for several yeas now, I have not run into a situation where I had to mess with it.

Here’s what you change.  And keep in mind, this is NOT the correct way to handle this on a production or public DNS server.  You’ll need to read up more on the correct config for this one.  But on my tiny LAN or at home, here’s what I did.  In the /etc/apparmor.d directory, edit the usr.sbin.named file.  Find the line:

/etc/bind/** r,

Change it to:

/etc/bind/** rw,

Then restart the apparmord daemon.  If your DDNS config in Bind and DHCP are correct, you should start seeing successful updates now.

Here’s a coulple links that were helpful on the DDNS setup:

http://brunogirin.blogspot.com/2007/11/dhcp-and-dynamic-dns-on-ubuntu-server.html
http://ubuntuforums.org/showthread.php?t=274665
http://www.ops.ietf.org/dns/dynupd/secure-ddns-howto.html

Also, I wanted to make a note to myself. Creating a new key for DDNS:

dnssec-keygen -a HMAC-MD5 -b 128 -n HOST dhcp-update-key

That creates keyfiles in which you’ll get your key string, this is added in your dhcpd.conf and named.conf.* files as “secret”.   RTFM dnssec-keygen. and read up on the links above. :)

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Help with Nettiverse naming, FaceBook.

by Greg on Apr.09, 2009, under Geek, Networking

Well I just have too much fun with things like this. I don’t know where it came from, but the Blogosphere was a great name people use. I suddenly thought of Nettiverse because I was trying to connect my blog with Facebook and Twitter. I thought they were pieces of the virtual universe we take part in, the Nettiverse. Now, many people out there are moving away from the Blogosphere and into the Twitterverse. Or maybe it should be called the Twittersphere. Personally, I like Twitterverse.

What’s bugging me is this, Facebook’s name. I haven’t seen or thought up a cool name for it as it exists in the Nettiverse. Anyone out there with a cool idea?

I thought of BookHole! Hahaha! I like it, makes me laugh because that’s exactly what it is, a Black Hole in the Nettiverse. Once you get in, you can’t get out! It sucks you in and wastes away time! But there must be something more fun to call it? Tweet me if you have any ideas. http://twitter.com/gregthegeek

By the way, as people more and more move away from blogs and on to Twitter, I’ve seen a post or two from people suggesting that blogs are a thing of the past. Well, I disagree. I feel they are useful tool. I use my blog mostly as a tech log. Things I like to remember, things I once fixed. The world out there could care less about it, but that’s not the point. It’s for me. I refer back to it, and it’s easy to get online while I am at a client and can’t remember how I solved a problem. Also, the little tidbits I post are found by Google searchers. So, if I find a solution and it helps just one person out there. Right on! Tweets are too short for that. So I like my blog, and I’ll keep using it alongside my Tweets and BookHole. (there’s got to be a better name than that! ??? )

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Configure Windows Server 2003 and 2008 w32tm commands on domain controller

by Greg on Apr.07, 2009, under Networking, Windows Server

This drove me nuts!  Why Microsoft had to take something totally simple in Windows 2000 and make it a complicated thing is NOT beyond me!  This is MS we’re talking about!  Of course it’s not easy with newer versions.

Took me a little bit, but here’s the commands I used on our primary domain controller, and it’s working great. that first w32tm command is all one line.

w32tm /config /manualpeerlist:”0.pool.ntp.org 1.pool.ntp.org 2.pool.ntp.org pool.ntp.org”,0×8 /syncfromflags:MANUAL /reliable:yes

w32tm /config /update

net stop w32time

net start w32time

w32tm /resync /rediscover

That should do it. However, always make sure you firewall is open to port 123 outbound!  I initially was receiving this error after running a “w32tm /resync” :

The computer did not resync because no time data was available.

In my case, that was caused by my firewall blocking port 123 for NTP traffic.  Go figure, we’ve been running this particular network for probably 2 years with that firewall blocking port 123, and only now did someone come and ask “why is our computer time off by 6 or  7 minutes?”  This is when you say, “Welcome to the world, can I help you?”  (Good old Beavis)  Well, at least we got our server configured better as a “reliable” time source with the right ntp.org pools.

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Exchange 2007 needs command line to set FQDN of external host name on Send Connector

by Greg on Aug.22, 2008, under Internet, Networking, Windows Server

In Exchange 2007, you have a nice little GUI to set your FQDN on your Send Connector. (Mine is called Outbound, as shown below.)

You can see my FQDN, set under the Hub Transport/Send Connectors of the Exchange Management Console.

However, if you send mail out to an external address, you’ll notice in the headers that your internal server name is still listed! What!? What’s the point of the GUI?

You have top open Exchange Management Shell, and type in a command to solve this. It’s easy.

As shown above, you just type in the command:

set-sendconnector “Outbound” –fqdn mail.1stbyte.com

Replace “outbound” with the name of your send connector, and of course, change to your own FQDN, not mine.

It will come back in error, or success. If success, you can check your headers on and external account right away.

Have fun!

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DFS links to shares on Windows XP SP2 do not work on local system

by Greg on Apr.18, 2008, under Networking, PC Repair, Windows Server, Windows XP

Well for the larger businesses out there, this may not be a useful tip. But for those of us that support small networks, like less than 50 or even 10 systems, utilizing shares on workstations is sometimes needed. For example, I have servers in most all of my networks, and their hard drives are fairly large, but I don’t want to save all my downloads and application CD’s on the server. With newer workstations loaded with larger drives than servers sometimes, I’d rather make use of that space there. Not with the main, business critical data, but only things that are not needed for backups or maybe read only archives. These 500+ GB drives give us a ton of space, and when you only have less than 10 people accessing this data periodically, this makes perfect sense. Constant read/write access with lots of users would require the server, rarely accessed stuff goes on a workstation.

Here’s the problem I ran into though. I like to use DFS and create a single shared, mapped drive for all the users. In there I might have a couple shares pointing to workstations. On XP SP2, this works fine, EXCEPT if you are accessing the DFS link from the system where the share resides. You will get an Access Denied error, even with all the correct permissions.

Here’s a registry fix that will overcome the issue.
(Remember, use the registry at your own risk. Back it up if you must. Heck, backup your whole system!)

Open this key on the XP system:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Mup\Parameters

Add a DWORD value:

EnableDfsLoopbackTargets

Change its value to 1.

Reboot the system.

Your share should now be working from DFS mapped drive from the local system. (the local system where the share is located.)

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Find an email address that already exists in Active Directory

by Greg on Apr.14, 2008, under Networking, Windows Server

So you went to add a new address to a user account in Active Directory, and you got an error that this address already exists? Sucks huh? Especially when you don’t know where it could be? Here’s one way to track it down.

On your domain root in AD Users and Computers, right click, select Find. Select Custom Search, click the Advanced tab, and enter an LDAP query like so:

proxyaddresses=smtp:emailaddress@youwanttofind.com

(I am assuming you are not a complete NEWB and you know you should replace that email with the one you want.)

Then click the Find Now button. You should see a in the results below any object that may have this address on it.

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New account does not appear in Global Address List but does in All Users

by Greg on Mar.27, 2008, under Internet, Networking, Windows Server

I’ve run into this a few times, thought I’d record the solution for once so I remember it.

After adding a new user account, the user does not show up in Outlook’s Global Address List, but does show in All Users. (If you click “To” in a new message, for example, and in the Select Names windows under “Show names from the:” drop down, you select All Users.) Even if I go into Active Directory Sites and Services and manually force replication it does not work. (under the NTDS Settings for each server) Normally, I would even go into Recipient Update Services and manually update, but this does not work either.

I found out that if you have Outlook in Cached Exchange Mode, the Global Address List does not update for up to 24 hours. I don’t know the details on that, but I can force it to update. This is on a per-machine basis, so doing this across the whole network won’t work. (Although, there may be a way to do this, I just don’t know how.)

Go into Outlook, go to Tools, Send/Receive, then click Download Address Book. Make sure you have Global Address List under the Choose Address Book drop down, and click OK. Problem solved.

By the way, I am using Exchange 2003 and Outlook 2003.

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Folder redirection user permissions block access to Administrators

by Greg on Mar.19, 2008, under Networking, Security, Windows Server

When using Folder Redirection on a Windows 2003 server, the default policy is allow only ownership and permissions to the user. No admin account would have access to this folder. For example, you create a Group Policy to redirect user’s My Documents folders to a home directory on the server. Once a user logs on and this policy is applied, the folder is created with ownership of the user only, and file permissions granted for that user only, too.

This has presented a big problem for me, having come from Windows 2000, where this was not the case. As you might guess, when only the user has permissions specified, no administrator can get access to this folder for backup purposes. Our backups always failed.

Well then, on Windows 2003 Server, two default policies are in place making the user’s folders more secure. Nice, but I don’t care. I want backup rights by default. Go into the Group Policy where you would like to define the new policy. I made a new Organizational Unit and put all my computers in there, so I could define the policy at a lower level, instead of at the domain level. Once into and editing you policy, drill down to here:
Computer Configuration –
Administrative Templates -
System –
User Profiles –

In here look for these two policies and enable them:
“Do not check for user ownership of Roaming Profile Folders”
“Add the Administrators security group to roaming user profiles”

Now this will allow Windows 2003 to behave more like Windows 2000 on the redirected folders. Unfortunately, there is one issue. It does not change permissions on previously created folders, only on newly created folders. That’s a pain, but not that big a deal, because I can probably script some folder moves and recreate them.

Also, even though this says “Roaming” in the policy items, they apply to local and roaming accounts.  So even if your users are normal, non-roaming profiles, you still need to set.  In my case, we did not have any roaming profiles and only used folder redirection OR simply had home folders mapped from the server.  Doing either of those had the same permissions problem and the policies mentioned solved the issue. (except for previously created folders, it only changes on newly created folders after the policy change.)

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Resetting NTFS permissions are not taking effect on child objects

by Greg on Mar.19, 2008, under Networking, Security, Windows Server

Recently I went to reset a user’s home directory permissions on the server to allow them full control over each file/folder in their home directory. I setup all the normal accounts and of course the actual user account, with Full Control. I then went into Advanced and selected “Replace permission entries on all child objects” and hit apply.

This seemed to work fine, except the user complained that they could not access the documents in certain subfolders. When I checked those subfolders, the permissions were correct, except for her account had no permissions specified. Essentially this means, no perms, no access. So I tried again, same result.

The solution was simple, though, I can’t figure out why this was configured this way. At the root folder you wish to start inheritance, go into advanced under security on that folder. Go into Advanced again, and under Permissions, highlight the user in question, and click Edit. Under the detailed Permission Entry window, at the very bottom is a checkbox for:

“Apply these permissions to objects and/or containers within this container only.”

Uncheck that! And apply the permissions once more. All child objects should now have all the correct permissions! Yay!

I don’t understand why this is set this way. Is there a Group Policy in place I don’t know about? Did a previous IT guy change that? At least I have a solution. J

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