User gets an error prompt "A system restart cannot be completed while another software installation is in progress. Please allow the software installation to complete before attempting a system restart."
Cause:
Under very specific conditions, the persistent job counter is not decremented when a job is finished. The coordinating system prevents these client computers from being restarted because it believes that a job is still running based on the JobCounter value.
Solution:
1. Stop the SMS Agent Host (CcmExec.exe) service on a System Center Configuration Manager 2007 SP1 client computer.
2. Location the following registry subkey and change its value to 0:
HKEY_LOCAL_MACHINE\Software\Microsoft\Sms\Mobile Client\Reboot Management\JobCounter
HKEY_LOCAL_MACHINE\Software\Microsoft\Sms\Mobile Client\Reboot Management\JobCounter
3. Start the SMS Agent Host (ccmExec.exe) service on the client computer.
Microsoft URL: http://support.microsoft.com/kb/970635/