Created, then deleted a POP account in Outlook 2010 - but it's still retrieving then deleting emails

Question

Such a weird thing... I created a pop account in Outlook 2010 for testing purposes while setting-up our new support ticketing system. I then removed that account in the normal way and restarted Outlook. When it restarted there was a message stating something like "Outlook cannot find the .pst file for this account"... even though that account had already been deleted..., so I closed Outlook, then checked to see if the .pst file was still there, which it was... so I deleted it, then restarted Outlook.

So now, that account is not present on the list of accounts, and there is no .pst file for that account, and yet messages for that account are still showing-up in the Inbox, AND, most importantly, Outlook is deleting the retrieved emails from the server, even though the account had been setup as a POP account, and by default the checkbox for leaving mail on the server was selected. Consequently, when this instance of Outlook is running, our ticketing system cannot retrieve emails from the server, because they are being retrieved and then deleted by Outlook... by an account that doesn't exist.

I've read all the threads I can find about this type of problem, but haven't found a real solution... other than to delete and then recreate the mail-user profile... which I would like some confirmation on before I move forward with anyway (e.g. are there any downsides, etc.).

Would this account info be cached somewhere? Is there an Outlook db I can access to get rid of it? Registry perhaps?

Any solid advice is appreciated - thanks!