In Mail, one mailbox for Recovered Message (AOL) keeps showing 1 very large message that I cannot delete. How can I get rid of this recurring problem, please?

Question

In Mail on iMac, successfully running OS X Lion, one mailbox on My Mac for "Recovered Messages (from AOL)" keeps showing 1 very large message (more than 20 Mb) that I just cannot seem to delete. Each time I go into my In Box, the "loading" symbol spins and the message appears in the "Recovered Messages" mailbox. How can I get rid of this recurrent file, please?
At the same time, I'm not receviving any new mails in my In Box, although, if I look at the same account on my MacBook Pro, I can indeed see the incoming mails (but on that machine I do not have the "recovery" problem).
The help of a clear-thinking Apple fan would be greatly appreciated.
Many thanks.
From Ian in Paris, France

Answer 1

Ian
I worked it out.
Unhide your hidden files ( I used a widget from http://www.apple.com/downloads/dashboard/developer/hiddenfiles.html)
Go to your HD.
Go to Users.
Go to your House (home)
there should be a hidden Library folder there (it will be transparent)
Go to Mail in this folder
The next folder ( for me ) is V2
Click on that and the next one will be a whole list of your mail servers, and one folder called Mailboxes
Click on that and there should be a folder called recovered messages (server) . mbox
Click on that there a random numbered/lettered folder -> data
In that data folder is a list of random numbered folders (i.e a folder called 2, one called 9 etc) and in EACH of these, another numbered folder, and then a folder called messages.
In the messages folder delete all of the ebmx (I think that's what they were from memory, sorry I forgot as I already deleted my trash after my golden moment).
This was GOLDEN for me. Reason being, when I went to delete my "recovered file" in mail, it would give me an error message " cannot delete 2500 files". I knew it was only 1 file so this was weird. Why 2500 files? Because if you click on the ebmx files like I did, hey presto, it turned out that they were ALL THE SAME MESSAGE = 2500 times. In each of those folders in the random numbers, in their related message folder.
Now remember - DONT delete the folder, make sure you have gone to the message folder, found all those pesky ebmx files and deleted THOSE, not the folder.
It worked for me. No restarting or anything. And recovered file. GONE.
Started receiving and syncing mail again. Woohoo.
Best wishes.