Running Thunderbird

Hi all,

Hows it going. I am having problems in running Thunderbird

Ever since I moved everything over to the hard drive, it won't run at all. So I went to delete it all together and it said

" Cannot delete parent.lock It is being used by another person or program. Close any programs that might be using the file and try again."

and the same with any file I tried to delete in the Thunderbird directory.

So I downloaded the newer version 1.5 RC1 same again, I redownloaded the 1.0.7 version and nothing. I have transferred these back to the USB, same thing. I would really appreciate your help. Thanks

IE I have Firefox 1.5, but he works fine off the USB and the hard drive