Typically the cache folder is in %USERPROFILE%\Application Data\PTC\ProENGINEER. However it could be elsewhere. In the script that starts Pro/E you can set the location of the cache like this: set PTC_WF_ROOT=X:\ProE_Home\PTC\ProENGINEER <-- that the new location for the cache folder You may not want to delete the folder, just move it to a backup folder (don't rename it). That way you can recover any data from it if necessary. There are a couple of scripts on the PTCUser website that will go through and rename the files to the original ProE names.