Yep - I use that function already in another log file. The particular one I'm talking about just requires one line per user, i.e:
@FullName, @IPAddress0, @DATE, @TIME, @UserID, @ProductType
A line of info is added to the file every time a user logs in. This would provide me with a history. How I extract it is not a big issue - it's writing it that is. I have over 600 users all concurrently logging in between 8:30 and 9am so WritePrivateProfile and WriteLine won't do as far as I can tell. I hope that answers all the Q's?