Windows server 2012r2 not showing Desktop after login

[hums005]

Hai,

 

My colleague accidentally edited the local policy of the server instead of the Domain policy(i think that was what happened) and now the server is pretty much locked out. We can't Remotely connect to it or even log in locally to server. Even powershell is showing access denied to administrator and gpupdate is failing saying username or password incorrect. None of Microsoft management console commands like gpedit.msc works. I have tried most of the fixes i found on google. does anyone have ideas as to what can be done short of reinstalling the whole server? We have used the backup to up another server already, so there is no time constraint to this. We would rather not have to start from scratch and would like to know what the fix is in case this happens again. 

 

have a good day guys.

[Wolly9102]

17 minutes ago, hums005 said:

Hai,

 

My colleague accidentally edited the local policy of the server instead of the Domain policy(i think that was what happened) and now the server is pretty much locked out. We can't Remotely connect to it or even log in locally to server. Even powershell is showing access denied to administrator and gpupdate is failing saying username or password incorrect. None of Microsoft management console commands like gpedit.msc works. I have tried most of the fixes i found on google. does anyone have ideas as to what can be done short of reinstalling the whole server? We have used the backup to up another server already, so there is no time constraint to this. We would rather not have to start from scratch and would like to know what the fix is in case this happens again. 

 

have a good day guys.

Specify what you mean by locked out: meaning it doesn't accept your password or showing a black screen? And what exactly did he change the local policy?

[hums005]

1 minute ago, Wolly9102 said:

Specify what you mean by locked out: meaning it doesn't accept your password or showing a black screen? And what exactly did he change the local policy?

i can enter the password for the administrator and log in. but instead of the desktop showing up, a black screen is shown. i can see the mouse pointer. Alt+ctrl+delete works and i can open task manager. I tried opening gpedit, msconfig, cmd, powershell etc through the create new task menu in task manager and CMD works as administrator and I can edit group policy files but when i try to perform gpupdate to apply the changes, error is shown.

 

none of the MMC commands work. anything with .msc shows the error and prompts to close the program

 

I think he was trying to modify the permissions for some users and when some error occured and accidently he unchecked all the users' checkmarks under permissions. this is what he told me. i dont exactly know how he did it.

[hums005]

thank you @Wolly9102 for responding. i dug a little deeper and asked exactly what he did. turns out he tried some random fix from google search for "Access Denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))" and later removed the ticks from every listed user's checkbox thinking that he was reverting the changes he made. 

 

upon further looking, i found https://social.technet.microsoft.com/Forums/windowsserver/en-US/07aead23-1fce-4c3d-8df9-f772aef4fad0/local-security-policy-hot-to-remove-dcom-values-and-restore-to-ampquotnot-definedampquot?forum=winserverManagement

 

i obviously couldn't go through GUI to access the security settings. but he had later found another fix

 

I found another solution here http://www.pcreview.co.uk/forums/thread-2364917.php 
It says you can try to edit the following registry key - but I haven't tested it.

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\DCOM\MachineAccessRestriction

 

luckily regedit was working and I was able to reset the value to 1.

 

The problem is fixed now. thank you LTT Forum.