Starting about 7-10 days ago, a few emails that are on the server that did not get downloaded into Pegasus 4.80. In case it's important, I am using custom URL in Google Workspace email.

Any suggestions?

Would go to Tools / Internet Options and click on the creat TCP Log.
Then run the connection.

It will create a log file that will have a lot of information that might give reason why those messages are not being downloaded.

File are in TCPLogs in the Mail Directory. Be careful to remove the password lines from files before uploading anything, since they will be in clear text. Even regular log file has encrypted passwords, but it can be decoded, but logs have it clear.

Might show something in logs.

Larry, is there a chance that they were downloaded but then filtered in some way. I ask because I know that with Google mail (gmail), the Google server keeps track of mail that is downloaded and doesn't make it available for download again, at least not that I have figured out. I am assuming that Google Workspace email works the same way but I'm not certain about that.

I have no filters enabled.
I searched all all content in all folders.
I searched the deleted folder.

Didn't find anything.

Do you think oauth could be involved? The sender uses gmail.com.

When I search for other emails that I know exist I'm not finding them, so I'm wondering whether there is a problem with indexing.

I don't think so. I have not seen any other reports of same.

Please confirm that I understand correctly that you can see messages on your Goggle Workspace inbox that were not downloaded by Pegasus Mail POP3.

That's correct.

In case it helps, I also use Outlook 365 desktop and the emails are downloaded into it. So it seems to be an issue only with Pegasus?

And it doesn't happen with all gmail emails.

I have a gmail account but have not experienced what you describe. I have however been frustrated by the fact of being unable to retrieve a previously downloaded message. With my other accounts I can use their web interface to empty the inbox except for the message I need, clear the Pegasus Mail record of previously downloaded messages, and then let Pegasus Mail retrieve messages. It will bring down that one plus any that arrived since I cleared the inbox. This procedure is not easy so is not for routine use but it has worked whenever I have needed it except with gmail.

The bottom line is that I don't have any thoughts other than something happened that left Google Workspace thinking that the messages had been retrieved. A filter of some kind is the only thing that comes to mind.

I can archive messages in the inbox of my gmail account. What is the procedure for clearing the PM record of preciously downloaded messages?

Clearing the record of previously downloaded messages doesn't work for gmail because it, not Pegasus Mail, keeps track of what is downloaded.

If you want to know the procedure anyways, the previously downloaded message record is stored in a POP?????.PM3 file. There is one .PM3 file for each POP3 configuration file (.PND). You must find the correct .PND file, inside of which you will find reference to its .PM3 file. You rename or delete the .PM3 file to remove the record of previously downloaded messages.

Sorry for this lacking details. I am traveling, short on time, and have spotty wi-fi so am unable to get into great detail. Things should be better in 24 hours so I can revisit this then if needed.