On several systems over the past year I have seen the C:\Windows\Temp folder filling up with large .cab files generated by the system, on a semi-regular bases. This continues until there is no available drive space and the system becomes unusable.
The short term solution is to just delete all of the files but the problem returns after weeks or months, depending on the initial free drive space.
It seems this is caused by a large log file within the C:\Windows\Logs\CBS folder. To resolve I created a folder C:\Windows\Logs\CBS_Archive and moved all CbsPersist_file_number.log files, older than 10 days, to the archive folder. This seems to have resolved the issue.
Are you having Terminal Server (Remote Desktop Services) performance issues when logging on, redirecting printers, or the print spooler hanging? Eric Guo has a recent post outlining these performance issues can be due to; “hundreds or thousands of Inactive TS Ports”…..”in certain scenarios on 2003 Terminal Servers and 2008/2008 R2 RDS Servers.” The first server I checked had hundreds. He has provided a tool “InactiveTSPortList” on CodePlex that will allow you to list and/or delete the inactive ports (requires Live ID sign in):
Direct link to Codeplex: