I assumed after I read an IM that it would remain in my inbox, but my inbox is empty now, I looked around but didn't see a default setting to keep messages.  I also assume that IMs that are gone are irretrievable.  Does that about cover it?

EE - the reason I am asking the above post is because I sent an USPS-MO off to a seller from an EE post and the thread dissappeared, I am assuming it got trashed but now without the IM or the post I don't know the screen name of the seller and only have their name and address.   The post was for a CavArms C1, bushie carbine handguards, & single point sling adaptor for $45 shipped.  I'd like to get the screenname of the seller if nothing else, but would also like the post content for proof of the transaction.

thanks.

I think it says on the Inbox screen that IMs are automatically deleted when read.  But you can save them off to the Saved folder if you want to keep them.