I had to set up 3 gmail accounts to access information on a government site. I was able to set up OAUTH for one of the 3 accounts but not for the other two, though I copied the setup information from the gmail account that works. The OAUTH button just doesn't appear. If I attempt to download mail I get the dreaded

POP3 error: -ERR [AUTH] Username and password not accepted.

I did find a workaround -- automatic forwarding--, but I'd really rather get my Gmail in Pmail directly. Suggestions?

(AI answer to "add multiple gmail accounts to another server": set up automatic forwarding from each account --from gmail account: Settings/all settings/Forwarding and POP/IMAP tab/Add Forwarding address). Do whatever Gmail says from there.

There is no OAUTH button so I'm curious what button you are talking about. If you mean the "Gmail" button, it should always be visible so that may something that needs specific attention.

Let me give you an overview about Gmail with Pegasus mail.

Firstly, you have the option of connecting using OAUTH2 authentication OR you can have Gmail provide you with an app password and use that instead of OAUTH2. Whenever I mention the app password option I always make it clear that we don't know if, or when, Gmail will stop supporting app password authentication. I am not aware of any indications that they. Their emphasis on using OAUTH2 keeps us wondering though.

Secondly, OAUTH2 authentication is specific to a Gmail address. So, if you have three Gmail accounts, you will need to use the Gmail button in Internet Options three times. Unfortunately, the Gmail button is dynamic, offering different options based on the email address in the "My Internet e-mail address is:" field. It is designed to work when there is a separate Identity for each Gmail address although I believe it should work by changing the "My Internet e-mail address is:" field to the Gmail address that you are setting up OAUTH2 for. I am not certain about this. I use separate Identities so have never tried it.

If you aren't familiar with Identities then that may be a place to start. There are valid reasons for separate Identities in your scenario, most importantly is that you can reply as the Gmail address the message was sent to. Multiple Identities adds some complexity to Pegasus Mail though. You can read about Identities starting on page 150 in the manual and in the "Identities" section of the Help file. The information is presented differently in each source so I suggest taking a look at both.

App passwords seem to be a thing of the past. However, I found that by using the Setup Wizard instead of what to me was the normal procedure of adding from the Internet Options windows (including establishing a new identity and adding a gmail address as above), Gmail finally admitted that I existed.

I'll address my other two problems in separate posts (this is to remind me): I can't send mail to either my velociter.net or gmail addresses from Pegasus and...

I know there's a way to make or access a log file but...

The Help suddenly quit working. A help window opens but it's blank.

I'm still using the app password with no problem.

You do need to go thru the web page of gmail, and have to allow pop3 and smtp.
By default they are disabled. Been a long time since I looked at the settings, but my app password does still work

99% of my email is thru my local ISP, but somethings don't like the guam.net domain, so use my gmail for those.