How to troubleshoot: Windows - Low On Registry Space : The system has reached the maximum size allowed for the system part of the registry. Additional storage requests will be ignored.

Windows Server 2003 RTM

Windows Server 2003 Service Pack 1

Windows Server 2003 Service Pack 2

In the System event log, you might notice the following information:

Type: Information
Date: MM/DD/YYYY
Time: HH:MM:SS
Event ID: 26
Source: Application Popup
User: N/A
Computer: <Computer Name>
Details:
Application popup: Windows - Low On Registry Space : The system has reached the maximum size allowed for
the system part of the registry.
Additional storage requests will be ignored.

The way that I would start troubleshooting is the following:

1) In Perfmon, you might want to do the following:

Add System > % Registry Quota In Use > __________

Check to see what the maximum value it is.

Add Memory > Pool Paged Bytes > ___________

Check to see what the maximum value it is.

2) Check the sizes of the registry hives in:

C:\windows\system32\config

Security ____ MB

Software ____ MB

System ____ MB

Default ____ MB

C:\Documents and Settings\

Default User ____ MB

LocalService ____ MB

NetworkService ____ MB

User Profiles # ____

Each individual User Profile sizes ____ MB (Sometimes the median and biggest size can be enough).

3) Please make sure that you don’t have the following registry key set:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control

RegistrySizeLimit

124594 Understanding and configuring Registry Size Limit (RSL)

http://support.microsoft.com/?id=124594

4) If you don’t have the registry key set, install the latest UPHClean in http://blogs.technet.com/uphclean/ .

i.e.

32-bit UPHClean v2.0 build 2.0.49.0 (beta)

http://blogs.technet.com/uphclean/pages/uphclean-v2-0-beta-build-2-0-49-0-for-32-bit-platform-operating-system.aspx

After installing UPHClean, set the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UPHClean\Parameters
SHARING_VIOLATION_REMAP (dword) 1 (hex)

Stop and Restart the UPHClean Service.

5)  If you still have problems, the information that you gathered in step 2 might guide you to an application or service or driver that is not unloading the registry keys.

Hopefully this will help you narrow down the cause of the warning.

References:

System Error Codes (500-999)
http://msdn.microsoft.com/en-us/library/ms681388(VS.85).aspx

2.2 Win32 Error Codes
http://msdn.microsoft.com/en-us/library/cc231199(PROT.10).aspx