Windows Vista Missing (D) Drive and (E) Drive?

1. Right click My computer and select Manage.
2. Click on Disk Management.
In the right hand window you should see all of your drives with their drive letter.
If you see a drive listed but without a drive letter that is likely to be your “missing” drive. To gain access try the following:
1. Right click the drive and select Change Drive Letter and Paths.
2. Click the Change button.
3. Select a Drive letter and click Ok.
Now check My Computer for the drive.