[AccessD] MDE Will not open (resent?)

I've got a user on the line. There is an A2K3 DB that opened this morning and now it give an error, "You can't convert or enable an MDE file." This happens whether we hit convert or open. It didn't even prompt for these when it worked this morning. I have no MDB....just the MDE...any options here?

I did not write this thing...I'm not getting a good answer on who exactly did...so I don't know much about it's origins.