Why does the Disk Cleanup tool in Windows XP and Windows 2000 hang when I try to start it?

Close all running applications.

From the Start menu, click Run and type

%temp%

to open the Temp folder on your computer.

Type Ctrl+A or from the Edit menu click Select All to select all the files, press Delete, then click Yes to the confirmation.

Close Windows Explorer.

Open the Control Panel Internet Options applet.

Select the General tab, then click Delete Files.

Select the "Delete all offline content" check box, then click OK.