- Open a command prompt. If you are not sure how to open a command prompt, click the Windows Start menu, type
cmd, and press Enter.
- in the Command Prompt window that opens, type
vol c:and press Enter.
- In the displayed output, find the 8-digit number listed as the Volume Serial Number for C drive. Make sure that the message is Volume in drive C is OS.
The case of the letters is not important and no dash is included. In this example, you would enter 12abcd34