When backing up your TomTom, it is safest to 'Show' Hidden Files first.

Under Windows 7 the procedure is differnt to that under Windows XP:

Click Start, the select Control Panel

Click to open Folder Options.

Click the View tab.

Under Advanced settings, click Show hidden files, folders, and drives, and then click OK.

That's it - otherwise follow the procedure detailed elsewhere under 'Tutorials'