Custom PowerShell PRTG sensor script

PRTG only run x32 PowerShell, so if you're having problems with the sensor returning "response not well formed <script> cannot be loaded because the execution of scripts is disabled on this system" you need to lower the execution policy in PowerShell to "remotesigned" in the x32 PowerShell. To do so navigate to C:\Windows\SysWOW32\WindowsPowerShell and run PowerShell.exe and then run the Set-ExecutionPolicy commandlet to set the execution policy there.

MS Exchange ActiveSync high CPU

If you're running Exchange 2010 and Symantec Enterprise Vault, after an archiving run when EV is removing the emails from Exchange it can greatly elevate the CPU utilization for the ActiveSync app pool on your CAS server. It will go back to normal once the emails are removed. It will also elevate the CPU utilization on the relevant mailbox servers.

CPU spiking on Microsoft Exchange Activesync

We had the MS Exchange ActiveSync app pool (W3WP process in task manager) spiking up to 99% and staying there. Recycling the ActiveSync pool only temporarily fixed it. It turned out that our HTTP redirect for OWA had been inherited by all virtual directories including the ActiveSync one. Due to a bug, this can happen even if you select not to apply the redirect to all sub-directories. Once we remove the redirect things started working again.

Error 6003 in Exchange 2010

We demoted one of our old domain controllers and our Exchange 2010 mailbox server started giving us a 6003 error every 5 minutes:

SACL Watcher servicelet encountered an error while monitoring SACL change.
Got error 1722 opening group policy on system <old DC> in domain <domain name>.

The only thing which ended up clearing it was restarting the server.