Hi all,
I want to convert to Pegasus from Postbox and want to know if there were any issues to be aware of from people who have done this. I have maintained complete email continuity since 1994 sticking only to email clients with human readable storage formats. So I am delighted to have learned about Pegasus, now that Postbox was bought and no longer maintained.

As I understand it, Postbox actually uses the mbox format so all I have to do is rename my Postbox files with a .mbx suffix and Pegasus will see, read and index them automatically.

I also have 2 primary email accounts with gmail, with one of them having 4 aliases/identities.

I don't know anything about Postbox but there was a long discussion back in August '23 about Thunderbird .mbx files and Pegasus Mail. It may be more confusing than helpful but I will link to it below.

The process, in simple terms, is to copy the Postbox mail files to a separate directory, rename them to add the .mbx extension, remove any spaces and special characters, and shorten to no more than 15 characters (15.3 form). That directory can then be added to the Pegasus Mail folder list as an added mailbox. Warning: At the end of the discussion referenced above is an explanation of a solution that worked which included that step of copying the mail files in to the PMAIL\ADMIN directory. I do not recommend doing this. Firstly, there is no PMAIL\ADMIN directory but there can be a PMAIL\Mail\ADMIN directory. Copying them into that directory intermingles them with the Pegasus Mail mailbox files. I would be better if they were kept separate so, IMO, a destination like PMAIL\Mail\Postbox would be better. This is the link to the August '23 discussion:
https://community.pmail.com/index.php?u=/topic/11937/import-email-folders-from-thunderbird/post-55745

As for your gmail accounts, Pegasus Mail uses the concepts of Users and Identities. This is the content of a post I recently made in another topic:

Separate Pegasus Mail "Users" means that the mail and the configuration settings are in individual running instances of Pegasus Mail. So, if you have three hosted email accounts, you could have three Pegasus Mail Users, each would only configuration settings and email specific to that Users. It is still just one Pegasus Mail program installation, but you can run multiple instances as different Users by using a combination of different command line options

Pegasus Mail "Identifies" are unique configuration sets within one running instance of Pegasus Mail. With Identities, all mail activity is visible within them however you can specify different configuration options for each one, like which SMTP host to use. You can easily switch between Identities and can assign a default Identity to an IMAP mailbox.

In summary, "Users" allow you to keep each one completely separate from the others while "Identities" allows you to switch between different configurations within the same running instance of Pegasus Mail.

It should be relatively painless to test since a test won't require that you first configure Pegasus Mail to be fully functional (eg: no internet configuration (POP3, SMTP, or IMAP) needs to be done yet).

Installation hints:

• It has been awhile since I have done a Pegasus Mail installation so don't know what the installer currently offers as options but...

  1. ... If you see an option that says something like "Preconfigure a mailbox", select it.
  2. ... if you see an option that lets you choose between single or multi user, choose "multi" even if you don't have any intention to set up multiple users. The multi-user installation creates a user named Admin by default but operationally, you don't know it. It maintains the ability to add a user should you ever want to, and, it uses a directory structure that I believe long-time users of Pegasus Mail find more natural to support.

• Be sure not to install Pegasus Mail anywhere in \Program Files, \Program Files (x86), or \Users. Windows file protections in those directories will prevent proper operation.

I'll just do a full conversion and setup. I have to eventually get off of Postbox and there's no other alternative that meets my criteria. For example, Mailbird and EMClient (the company that bought Postbox) use binary storage formats for the mail which is a nonstarter.