[AccessD] LDB File, Orphaned Logins

Hello all,

I have a database that has been working for almost 2 years now with no
trouble.  It is split, with security.  Both BE and FE share same MDW file.
There have been no changes to this database for about a year.  Recently the
users are complaining about it becoming slow.  I looked into some things,
compressed and repair FE and BE.  Still no luck.  

I noticed that even though everyone was out of the database that there were
still LDB files (1 for BE and 1 for MDW) left on the server.  I opened them
in notepad and saw about 8 users still logged in, 5 of which were the same
person.  I tried to delete the LDB files, of which I got an error "cannot
delete file due to a sharing violation".  I have never had a corrupt
database or LDB file, I'm hoping this isn't my first as this is a fairly
large and complex database.  

Any help on how to clear these users out of the LDB File would be greatly
appreciated.  

Thanks,
Rich