Hi. I have about 200 emails in New Mail, all marked as read. However, only a few move to the Main Folder each time I close Pegasus. Ideas?

What comes to my mind is that read messages are allowed to remain in the new mail folder and the moves are the result of a on-close new mail filter rule.

Check for a new mail filtering rule that is applied when the folder is closed, and check that the "Allow read messages to stay in the new mail folder" option is not enabled. This setting is in Tools > Options > General settings > Basic settings.

Hi Brian. I don't have any filtering rules and the Allow... option is not enabled. Also, a few of these emails actually do get moved each time I close the programme,
On starting, it sometimes says a folder is locked

Also, the destination folder that serves as the default mail folder is defined in Tools > Options > General settings > Basic settings. I suggest using the "Select folder" button to select the Main folder again. I don't have much confidence that this will help, but it certainly won't hurt.

The "locked whatever" notice has only appeared about twice, then it sorts out its folders. There is no one else using this computer or another instance of PM running. Is "abend" what you meant? - I've no idea what it is.
I've been to Tools>Options>General settings>Basic Settings again and Select Folder takes me straight to Main Folder. Anyway, I set it again manually, with no success.
If I reinstall PM over the current one, might this help? Alternatively, can I uninstall it and reinstall it without losing my old mails? I use PM to keep copies of every email in case I ever need them

The "locked whatever" notice has only appeared about twice, then it sorts out its folders. There is no one else using this computer or another instance of PM running. Is "abend" what you meant? - I've no idea what it is.
I've been to Tools>Options>General settings>Basic Settings again and Select Folder takes me straight to Main Folder. Anyway, I set it again manually, with no success.
If I reinstall PM over the current one, might this help? Alternatively, can I uninstall it and reinstall it without losing my old mails? I use PM to keep copies of every email in case I ever need them

"Abend" = Abnormal end. This would be anything that prevents a program from completing its shutdown routine. Pegasus Mail does a lot during shutdown, included releasing the lock designed to prevent simultaneous access to a mailbox directory.

Unlikely. Your issue likely in a configuration file. A reinstall would not touch them, it only overwrites program files.

Yes, however the normal process is to do a new installation and then replace its mailbox with the one from the previous installation. The problem is likely in the mailbox directory so would be transferred to the new installation. A last ditch effort would be to do a clean installation and then copy just mail data (no configuration files) to the new installation. I don't think we're there yet.

Have you tried selecting all of the read messages and manually moving them to the Main folder?

How big is the Main folder? Could it have reached the 2GB file size limit? To check this, right click on the Main folder in the Folder list then select Folder information. I there will be the filename for the Main folder (default is "main.PMM" but it could be different). Make note of that filename then use a file explorer to navigate to the mailbox directory and look at the size of the file.

A couple things.
The Mail Lock message means that Pegasus did not shut down properly that last session.
When a session is started a file name MAILBOXP.LCK is created in the Mail folder with a 0 byte size.
It is removed if the program shuts down correctly. It can be left if Pegasus crashes or the system goes down for some reason that doesn't allow the proper closing.

It also happens if you try to open Pegasus twice at same time.

Second thing. New Mail folder is not actually a regular PMM/PMI folder, it is a collection of the CNM messages currently in the MAIL Folder.

The Main Folder is generally the default folder that is created by Pegasus Mail, and default is that messages opened are then moved to it after being opened, But there are options to allow them to stay as CNM files, and also be filtered to other folders or manually moved.

Not aware of option to open main folder on startup? There is a basic option to have it open newmail folder (CNM files), and that is listed at the top of list.

Reinstalling probable wouldn't make any problems.
But would always make a backup of everything in C:\PMAIL to be sure.

Uninstalling and reinstalling could have issues depending on setup.
If you have single user setup or multi-user setup.
In single user setup the Mail and settings are usually in C:\PMAIL\MAIL directory.
In multi-user setup the Mail directories are subdirectories C:\PMAIL\MAIL\ADMIN (example).
If you do install and the C:\PMAIL\MAIL exists it will pick up the settings.
If you remove that directory, and do a clean fresh install it will use the default setup, and you would have to manually copy old files, and if it doesn't agree could have problems.

Again. CNM files are the New Mail messages that have not been moved into a folder.
PMM and the messages in a folder, and the have a matching PMI (Index file of PMM files)

I use preview option, but you may have a different setup.
Good Luck.

Hi Brian,

I think something abnormal is happening on shutdown - I have to click the X in the top right corner twice to get the whole thing to close.

I went to Main Folder and checked consistency and get the master file error below.

The mail box file is 185 Mb.

I have a lot of CNM files - is this normal?

I can move all the emails
from New Mail to Mail Folder manually

Edit I reindexed to Mail Folder and it no longer gives the master file error

Does this happen on every close?
Can you tell if anything is happening after the first click?

What version of Pegasus Mail are you running?
Do you have any attached mailboxes (eg: a directory attached as an added mailbox)?

There will be one .CNM file for each message listed in the new mail folder.

Let us know when you have confirmed whether this solved the original problem of read mail not moving automatically

Hi folks, I don't know if I had this before, but I looked at my folders yesterday and I had no Mail Folder! And I had six folders named as lots of vertical stripes. I've now added a Mail Folder and copied the contents of these weird folders (emails later than Main Folder24) to it, but I'm having a mental blackout on how to make Main Folder the Home Folder, something I've done dozens of times before, but I've gone blank. Could some kind person explain how to do it?
It's currently set to Default. Pegasus is on the D drive.
I thought there used to be some sort of dropdown box where I selected Main Folder

Would look at these files in your mail directory.
C:\PMAIL\MAIL>find "Main Folder" HIERARCH.PM

---------- HIERARCH.PM
0,0,"0694FC35:664D:MAIN","024B349:My mailbox","Main Folder"

C:\PMAIL\MAIL>find "Main" Pmail.ini

---------- PMAIL.INI
Default mail folder name = Main Folder
Default mail folder name = Main Folder
Default mail folder name = Main Folder

The PMAIL.INI in your Mail Directory should have a line for each identity.
I have 3 in my folder.
The HIERACH.PM should have line showing which folder that points to.

Usually they are MAIN.PMM and MAIN.PMI
03/14/2026 04:01 AM 430,199 MAIN.PMM
03/14/2026 04:01 AM 1,652 MAIN.PMI

would make a copy of them to other location (with Pegasus Closed).
Possible the index file has been corrupted? Could try to rename it to something link MAIN.PMIX.
Then start Pegasus, and see if it would create a new one.
Think there was an old program in the PM350 (DOS) called PMSORT that would create index files, but not even sure it is compatible
17376 Aug 26 1993 PMSORT.EXE
But believe WINPM will just recreate the PMI file if it doesn't exist.
Will loose some info that is stored in the PMI file like messages read/unread. But the real index data should be recreated.

Mine Main folder is very small, so what is the size of yours. Think it has a 2G limit on the MAIN.PMM file.

I generally move messages to other backups every so often.
03/14/2026 04:01 AM 1,652 MAIN.PMI
03/14/2026 04:01 AM 430,199 MAIN.PMM
02/01/2026 06:11 AM 66,316 MAIN2003.PMI
03/09/2026 09:43 AM 3,883,411 MAIN2003.PMM
03/05/2018 01:05 AM 142,190 MAIN2004.PMI
03/09/2026 09:43 AM 25,795,255 MAIN2004.PMM
03/05/2018 01:05 AM 186,322 MAIN2005.PMI
03/09/2026 09:43 AM 11,316,316 MAIN2005.PMM
03/05/2018 01:05 AM 18,998 MAIN2006.PMI
03/09/2026 09:43 AM 1,481,627 MAIN2006.PMM
03/05/2018 01:06 AM 103,722 MAIN2007.PMI
03/09/2026 09:43 AM 8,007,387 MAIN2007.PMM
03/05/2018 01:06 AM 22,656 MAIN2008.PMI
03/09/2026 09:43 AM 1,921,887 MAIN2008.PMM

Just a possible issue. Good Luck.

Thought of another thing after above post.

169472 Apr 17 2011 MBXMAINT.EXE
180736 Apr 17 2011 MBXMAINT_UI.EXE
are in the PMAIL/Programs directory. From 2011, but might have some options. But getting the sizes for the MAIN.PMM and MAIN.PMI files might give info. Especially if it is at the 2G limit.

If it is over 2G, could probable split the file info pieces to retrieve data, but would require using a program that could handle the non-text parts.
But that would be interesting.

This can often be fixed by restarting Pegasus Mail. It seems to be the result of some sort of anomaly occurring while the folder list is being created. A rebuild of the folder list can fix it.

As for the default mail folder, that configuration setting is in Tools > Options > General settings > Basic settings. Use the "select folder" button to select the current Main Folder regardless of what is currently showing in that field.

Tom, the issues you have reported in this discussion have me wondering if your antivirus product could be interfering with the normal operation of Pegasus Mail. Have you checked to make certain that your mailbox directory is excluded from active scanning?

I removed Bitdefender a while ago and just use Defender now, as it was causing problems in Thunderbird

The AV product being used doesn't make a difference if it does active scanning, which Defender does. I strongly suggest that you exclude the mailbox directory (ies) from active scanning. If you don't know where they are, use the Info button in Help > About Pegasus Mail. The resulting display with contain entries showing the path to the Home and the New mailbox directory. You may need to do a web search for specific instructions on how to exclude folders in Defender for whatever version of Windows you are running.