I've moved it to a new folder. Any other Unknowns I've ever had have been when I've tried to view new mail before it's finished downloading, but they go into the normal Inbox (having lots of post flood things here today and have to keep re-posting)

As far as I can remember, my junk file folder has always been emptied manually when i felt like it. Suddenly, it seems to have decided to do it itself when I don't want it to, and I can't find an option to stop it. Can anyone point me in the right directions. please?

Do you have a folder-open or folder-close filter set assigned to that folder that is doing deletes?  To check for an assigned filter set right click on the folder name and look for a check mark beside the "Attach folder-open filter set" and "Attach folder-close filter set" options.

Thanks for the reply. No - nothing checked. Also, I don't tend to open or close that folder anyway in the normal run of events

Curious.  Are you seeing the message count for that folder increase in the folder list and then out of the blue it zeroes out without you opening the folder?

Have you checked the folder consistency and reindexed? 

Does the folder get large enough to be hitting the 2GB limit?

[quote user="Tom Barkas"]As far as I can remember, my junk file folder has always been emptied manually when i felt like it. Suddenly, it seems to have decided to do it itself when I don't want it to, and I can't find an option to stop it. Can anyone point me in the right directions. please?[/quote]

Is the check block in Tools, Options, Advanced settings marked to allow deleted messages to remain between sessions?

Hi Bfluet,

Normally, it increases (I never have many junk files normally - maybe 10 to 20)  and they stay there. Yesterday, I dropped to a small number and today to 1.

Have just done a re-index and corruption check - nothing noticeably different.

Some of my folders have several 1000 messages - we're talking about a few dozen here. 

Hi, Jerry,

It's not deleted messages - it's junk messages  - I have a folder where junk mail gets diverted to (and normally stays there till I delete it).

I've just noticed I have  a junk file from Unknown, Subject (None), no date and 10k - could this be doing something? 

The junk message from Unknown is certainly a malformed message so you want to get it out of that folder to see if it is the cause of the problem.  Moving it into another folder is not a good idea so you can either delete it or if you are curious what it is, use the "Add mailbox to list..." function to add a directory to the folder list and move the message to it.  This will place the message file (.cnm) in that directory where you could look at it with a text editor.

[quote user="bfluet"]The junk message from Unknown is certainly a malformed message so you want to get it out of that folder to see if it is the cause of the problem.  Moving it into another folder is not a good idea so you can either delete it or if you are curious what it is, use the "Add mailbox to list..." function to add a directory to the folder list and move the message to it.  This will place the message file (.cnm) in that directory where you could look at it with a text editor.
[/quote]

I've moved it to a new folder. Other times I've had Unknows, it's because I've tried to view incoming messages that haven't finished coming in yet, but they go into the normal Inbox