Win8升級安裝後刪除windows.old

1. Open Disk Cleanup by clicking the
   Start button . In the
   search box, type Disk Cleanup, and then, in the list of results, click
   Disk Cleanup.

   If you're prompted to choose a drive, click the drive you just installed
   Windows on, and then click OK.

2. In the Disk Cleanup dialog box, on the
   Disk Cleanup tab, click Clean up system files.

   If you're again prompted to choose a drive, click the drive you just installed
   Windows on, and then click OK.

3. Select the Previous
   Windows installation(s) check box, and any other check boxes for the files you want to delete, and then click
   OK.

4. In the message that appears, click Delete Files.