The DLL is the file apparently causing the problem, ATL71.DLL. To locate
the folder, do a search for the file itself. Click start, then Search.
Then you'll have to improvise a bit because I don't have XP and don't know
exactly how the rest goes, but what you want to do is get to the
file/folder search and key ATL71.DLL into the name box, then initiate the
search. The search results should show at least one file by that name and
the folder in whihc it resides. The name of that folder should give us a
clue to the application responsible. In my case, the folder is
"D:\Program Files\Sunbelt Software\CounterSpy", so it's pretty obvious
where my copy came from.
Since you're using XP, you shouldn't be seeing that message at all.
Identifying the application will provide a clue as to how to get help.