USB drive won't go

I was been particularly stupid one day, trying to repartition my backup USB drive without first backing it up.

Yes I know I was stupid ,and frankly I probably deserved to lose everything, but I was lucky. The drive woulldn't appear on my laptop, and yet after running all the windows diagnostics , I could find no problems.

Running the following prog solved the problem

diskmgmt.msc

Select a drive letter and away you go.