Open Computer Management by clicking the Start button Picture of the Start button, clicking Control Panel, clicking System and Security, clicking Administrative Tools, and then double-clicking Computer Management. Administrator permission required If you’re prompted for an administrator password or confirmation, type the password or provide confirmation.
In the left pane, click Disk Management.
Right-click the drive that you want to change, and then click Change Drive Letter and Paths.
Do one of the following:
To assign a drive letter if one has not already been assigned, click Add, click the letter that you want to use, and then click OK.
To change a drive letter, click Change, click Assign the following drive letter, click the letter that you want to use, and then click OK.
To remove a drive letter, click Remove, and then click Yes to confirm that you want to remove it.