unlinking accounts where a link cannot be found

Hello. I am trying to delete unused accts and I am unable to delete a 2000 acct as I get a message saying it must be unlinked first. When I go through the usual method of unlinking using Wizard then Linked Accts this particular acct is not listed anywhere as a linked acct. Any ideas on another method of finding out where/how this acct is linked so that I can unlink it (so it can be deleted)?