Delete windows. Old

Windows 7 crashed today and was reinstalled with a CD. As a result, two options are displayed at startup. After selecting the first option to open the file, a windows. Old file exists under drive C, occupying dozens of GB of memory. How can this problem be deleted?

1. Click Start to open Disk
   Cleanup ). In the search box, type Disk Cleanup and click "Disk Cleanup" in the result list ".

   If the system prompts you to select a drive, click the drive to install windows, and then click OK ".

2. On the "Disk Cleanup" tab of the "Disk Cleanup" dialog box, click "clear system files ".

   If the system prompts you to select a drive again, click the drive to install windows, and then click OK ".

3. Select the "previous Windows installation" check box and any other check boxes corresponding to the file to be deleted, and then click "OK ".

4. In the message that appears, click Delete file ".

All right, the windows. Old file is successfully deleted. However, two options are displayed at startup.

Right-click my computer, select Properties, select "advance system setting", and select "Startup and recovery) "" setting ", click the drop-down list of" default Operating System "on the" system startup "tab. Two start items are displayed, you can set the time here. This step still cannot delete one of the startup items,

Next,

Run ---> input msconfig ---> boot, select the old window system, and delete it. OK, restart.