Question : What is the source of this error in the windows registry?

Hello!
     I'm running windows 2003 server (NON DOMAIN CONTROLLER) service pack 2 and i saw this info in event viewer today while machine was locked:
source "application popup"
event ID 26
"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. "

I ran NTREGOPT program to have a look at the registry and i got this error:
"hkey_local_machine\security error reading the values contents"

so i went to hkey_local_machine\security and double clicked on the only entry there...there weren't
any subfolders or subkeys..just one key that said "default"  type was REG_SZ and the data was "value not set"
but when i double click on it it says:
"cannot edit: error reading the value's contents"

I checked another windows 2003 server that i'm not getting any errors from and it's the same way..just one key and i can't edit that value.  is this normal or what?  can someone shed light on these errors for me?  i'm almost afraid to reboot the server to be honest!

Thank you!

Answer : What is the source of this error in the windows registry?

Did you check this MSKB article around how the registry size was limited in previous Windows versions:-

http://support.microsoft.com/kb/124594/

It may be worth checking to see if the Registry Key:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Memory Management

as the size of the page file may still impact upon your situation.  Also it may be worth check these steps to see if the RSL may have somehow been set:-

1. Run the Registry Editor (REGEDT32.EXE).  
2. Locate the key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control.  
3. Modify the value RegistrySizeLimit (create it first it if it does not already exist) to reflect the desired size, in terms of bytes.

Hope this helps.