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Thunderbird mac migration from High Sierra to Big Sur

  • 5 replies
  • 1 has this problem
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  • Last reply by Stans

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After an Apple repair I've received my machine back with Big Sur installed. When migrating my emails from my backup to a fresh install of Thunderbird copying and replacing the Thunderbird folder with correct profile isn't resulting in any emails being populated.

Even though I paste and replace a profile that ends .default-release remains which seems to be where any accounts are added.

I've had to click settings on Local Folder and point to my other profile's local Folder backups so now I'm running off two profiles essentially.

This feels like a funky setup.

In the past after a restore I've just replaced the profiles and everything has worked. Is this something to do with Big Sur, is there a new procedure I should have followed?

Any help appreciated.

PHIL

After an Apple repair I've received my machine back with Big Sur installed. When migrating my emails from my backup to a fresh install of Thunderbird copying and replacing the Thunderbird folder with correct profile isn't resulting in any emails being populated. Even though I paste and replace a profile that ends .default-release remains which seems to be where any accounts are added. I've had to click settings on Local Folder and point to my other profile's local Folder backups so now I'm running off two profiles essentially. This feels like a funky setup. In the past after a restore I've just replaced the profiles and everything has worked. Is this something to do with Big Sur, is there a new procedure I should have followed? Any help appreciated. PHIL

All Replies (5)

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The procedure hasn't changed as far as Thunderbird's data (profile) is concerned. All you have to do is:

  1. Open the new profile folder abcdefgh.default-release
  2. Quit Thunderbird and make sure it's not running in the background
  3. Empty the new profile folder
  4. Open the backup profile folder ijklmnop.default-release
  5. Copy the contents of backup profile folder to new empty profile folder
  6. Launch Thunderbird
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Thanks Stans.

This is what I tried initially, but once I delete the default-release profile and copy in the back up profile, then open up thunderbird I get the following error message

"Profile Missing: Your Thunderbird profile cannot be loaded. It may be missing or inaccessible."

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The problem is that you deleted the actual profile folder (instead of just the contents, leaving the profile folder intact). This is a mistake lots of people do. Let's say the new Tbird installation created a new profile folder named abcdefgh.default-release, you're NOT supposed to delete that folder. You're supposed to delete and replace its CONTENTS with those from the backup, so that when Tbird launches, it still finds that same profile folder, whose contents have been replaced by the backed up stuff.

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Thanks for that explanation. I followed the thunderbird help docs which suggested to replace the Thunderbird folder - https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer#thunderbird:mac:tb78

So in theory should I be able to replace the contents of my backup profile.release and put it in the abcdefgh.default-release (ie replace the contents)

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info5409 said

Thanks for that explanation. I followed the thunderbird help docs which suggested to replace the Thunderbird folder - https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer#thunderbird:mac:tb78

That article hasn't been reviewed in a long time.

So in theory should I be able to replace the contents of my backup profile.release and put it in the abcdefgh.default-release (ie replace the contents)

Yes. This is my recommended and preferred method because it keeps things simple and straightforward in my opinion.