I believe this folder is just an archive folder which stores messages there which have been resolved to a local mail server. I believe they have been send and it's just a record of a few mails that meet the above criterea.
Not sure I understand. I thought the folder was where CDONTS puts mail before it is to be sent. Once sent, the SMTP server removes it or puts it in the BadMail / Queue folders. (I could be wrong - I just assumed this.) If I pause the SMTP service, send an email in ASP, it appears in the drop folder. When I restart the SMTP service - it disappears from that folder. I just find it odd that there are some very old emails in there. The emails in the folder definately should not resolve locally.
Sorry I didnt get back to you on this. I have read an article which suggests the Drop folder is used when you create a domain alias on the SMTP server. It assumes that email in there will be collected by another mail server and sent as needed.
What it says to do if this happens is to remove the alias, stop and start the SMTP and move the emails from the drop folder to the pickup folder.
Does this sound like it might cover what you were looking for?
You are a small minority, I'd say upwards of 99% have trouble understanding email. So many have hosted sites and complain that our mail servers are not sending them mail notifications. They fail to realise that our mailservers are probably the only part of our system that never goes down and the problem is always on their servers.
They always want proof of this and I always have to spend half an hour showing them DNS reports or failed emails.