Can not format Sandisk Sansa View...

First I hade problem when I tried to delete audio book, cold not delete those using Sansa View, could not delete those using computer (“No connection”). Because memory was full I decided to format the whole disc and load new music.

Now problem is that I have 194 empty  folders (“Unknown artist”) that I can not remove, I guess that it is for every record I had. I have not been able to remove those using computer (have now tried Vista and XP, different modesand Windows Media Player) and those folders are still there! Message is always same “No connection to player”. Then it sounds like a minor problem that for some reason I can not load new songs there either…

Any hints?