This error is occurring on the Policy Server (smps,log):
The Policy Server uses the following registry key to set the frequency it performs session store maintenance. Session Store maintenance is basically the clearing out of stale sessions from the store. The frequency is configured in the following registry key:
Windows: run 'regedit.exe'
This message will occur if there are multiple policy servers connecting to the session store. The message indicates that when the policy server attempted to perform session store maintenance, it found that another policy server was already in the process of doing session store maintenance. This process locks out other policy servers from attempting to execute the same maintenance at the same time.
Release : 12.8
This message is expected and can be ignored.