Slow logon on XenApp servers

Many XenApp administrators experienced strange issue that logon process is unexpectedly slow when users log on to the XenApp servers.

This issue may occur if RSoP logging is enabled and there is a large WMI repository on the problem Windows client or Windows Server computer. The WMI repository is located on the following path: %windir%\System32\Wbem\Repository

The Windows WMI repository can become corrupted or increases in size on Windows servers being used with XenApp. WMI corruption can cause problems for monitoring systems, and potentially some applications. You can rebuild the repository, but that may lead to other issues, and it doesn’t fix the underlying problem.

The problem occurs on systems that have many people logging into them, and hence a large amount of GPO logging. This logging affects the WMI repository, causing it to grow considerably, and sometimes get corrupted.

The RSoP logging process to the WMI repository causes delays to console logons and especially Remote Desktop logons.
Larger WMI repository sizes in %windir%\system32\wbem\repository cause longer logon delays.

You may disable GPO logging by editing GPO that gets applied to this server.

Go to Computer -> Administrative -> System -> Group Policy. Enable the setting “Turn off Resultant Set of Policy Logging.” Apply that, and you should get no corruption in future.

Now you need to rebuild WMI repository, create .bat file -> edit the file with notepad and write the following:

@echo off
net stop winmgmt /y
Ren %windir%\system32\wbem\repository repository.old
Ren %windir%\system32\wbem\mof mof.old
net start winmgmt
cd /d %windir%\system32\wbem
for %%i in (*.dll) do RegSvr32 -s %%i
net start "SMS Agent Host"
net start "IP Helper"

Save the file and run it as administrator.
Note you can also check your repository state with “winmgmt /verifyrepository”. This won’t make any changes, but will tell you if there are any known issues.

Refrence: https://support.microsoft.com/en-us/kb/2020286