Mail Archiver 5.1.5 fixes a couple of minor bugs including some fixes for Catalina.

  • Fixed a problem where the full hard disk access wasn't recognised on Catalina.
  • Emails are moved again to the trash for Imap.
  • Fixed another problem with the installer on Catalina.
  • The wizard no longer gets confused when clicking the app icon.
  • The trash mailbox wasn't always recognised for IMAP.

On Catalina

The press is either love, peace and harmony or gloom and doom. They only report the new features of Catalina. But I haven't seen anything about the problems that Catalina has:

  • The new "improved" security is just awful. It's only window dressing. For me as developer the security is even more intrusive than before. For you as user this may be a bit different.
  • I have never ever before seen a macOS beta with so many bugs. I still can't properly unzip many files without getting an error message. I made Finder crash with selecting a file. The communication between Apple and the developer never was great. During the Catalina beta there wasn't even that. Some bugs were fixed. But I had to check the bugs myself instead of getting a notification from Apple.
  • A lot was changed internally. The growing pains of that combined with the new security meant a lot of fun and may cause some rough edges in other apps.

Please update to Catalina with a plan:

  • Make sure you have replacements for your 32bit apps or run those in a Mojave VM.
  • Most likely all your system utilities will need to be updated to the latest version: Alfred, Find Any File etc.
  • Don't update in a hurry.
  • Backup! 2 backups are better than one backup. Make sure that your backup app works on Catalina, too.
  • Mail Archiver, too, will have to be the latest version.

Tidbits has a more detailed article.