The reason for receiving this error message is due to fact that OS contains an older or corrupt version of the PSAPI.DLL file. To solve this problem, if you use Vista, try to copy this file from another computer and save it in this folder: \Windows\system32\. For WINDOWS XP users, make sure that the OS is currently using latest patch SP2 which you can get it from latest Windows updates. If problem persists, please contact Microsoft for further assistance on how to update "PSAPI.DLL" file.