I have problems with "Compress Old Files". When I run disk cleanup, deleting old compressed files takes a long time and may not finish after an hour. Reza Masoudi
Compress Old Files is a feature of the Disk Cleanup tool (cleanmgr.exe) in Windows XP, but it does not delete files. What it does is take files that have not been accessed for a specified number of days and compress them to save disk space. This wasn't a bad idea when hard drives were small and expensive, but it's not such a good idea now.
The files that benefit most from compression are things like Microsoft Office files, and these are already compressed as standard when saved in the new Office 2007 and OpenOffice file formats. The files that take up most room -- sound, image and video files with extensions such as jpg, mp3 and avi -- are already compressed. Trying to compress them further takes a long time and they can end up larger than they were before. If you're really short of disk space, it's better to back up some large files to CD or DVD then delete them. External hard drives are an even handier option, but these should also be backed up.
Disk Cleanup can also perform a number of functions such as removing temporary internet files, removing downloaded program files such as ActiveX controls (not always a good idea), removing restore points (a bad idea) and uninstalling Windows components that you don't use (possibly a bad idea). As such, it provides a useful one-stop shop for people who don't want to be involved with the operation of their PCs. However, I think it's better to get slightly involved and download CCleaner from ccleaner.com, which does most of the same jobs. If you need to compress files, you can do this separately.
Bear in mind that Windows XP needs lots of disk space to store its swap file (code that temporarily doesn't fit in memory), hibernation files, temporary files, directory entries etc. You should always try to leave 2GB of hard drive space free, and never less than 1GB, to keep XP running at its best.
