Windows XP & Windows Server 2003 provide buil-in zip support, which treats zip files as regular folders. This means that zip files appear in Windows Explorer folder tree. This feature is rather attractive when having a few zip files in one folder and imposes no additional workload to windows PC. Problems arise when you have a large number of zip files in one folder. Windows will try to enumerate the contained files (that is scanning the zip files) and in large number of archives, CPU workload is rather intensive. To make things even worse, Windows search capabilities will force crawling zip files that requires even more CPU time.

To disable zip built-in support follow the below instructions:

Windows XP

• Unregister the ActiveX server that provides built-in zip support
• Rename the ActiveX server (you can register it again to restore zip support - you should rename it to its original name first)
• Run WinZip (or any other third party utility) to reassociate zip files extension

Windows Server 2003

• Unregister the ActiveX server that provides built-in zip support
• Renaming the ActiveX server doesn't help, since the file is protected by Windows (Windows system files protection system, will restore the original file)
• Run WinZip (or any other third party utility) to reassociate zip files extension

Unregister ActiveX server

Register ActiveX server

Note: You can use these tools to easily register / unregister ActiveX DLLs.