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What are the minimum files I need to recreate a user profile?

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  • Last reply by Ben

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What is the minimum set of files that I can recreate a TB user profile from?

For example, the official docs say to backup/migrate a user profile by copying the whole directory, but the `ImapMail/` directory can be dropped as it will automatically be recreated and any emails re-downloaded.

I remember seeing a post in an old support thread a while ago that said only a few files were needed (off the top of my head, possibly `cert9.db`, `extensions.json` and `prefs.js`), but I can't find it again now to double-check.

So, what files do I need to copy over to a new user profile to retain my:

  1. extensions and their preferences
  2. preferences
  3. email account settings
  4. calendar account details
What is the minimum set of files that I can recreate a TB user profile from? For example, the [[Profiles - Where Thunderbird stores your messages and other user data|official docs]] say to backup/migrate a user profile by copying the whole directory, but the `ImapMail/` directory can be dropped as it will automatically be recreated and any emails re-downloaded. I remember seeing a post in an old support thread a while ago that said only a few files were needed (off the top of my head, possibly `cert9.db`, `extensions.json` and `prefs.js`), but I can't find it again now to double-check. So, what files do I need to copy over to a new user profile to retain my: # extensions and their preferences # preferences # email account settings # calendar account details

Modified by Ben

Chosen solution

I could create a fresh user profile and manually set the extensions/bookmarks/preferences up again,

While this is a real pain, it's what I'd do though.

if possible I would like to copy across the minimal config details and let Firefox handle everything else.

I don't think it's that simple. Basically the entire configuration is in the file prefs.js. But it's not enough to just copy over the file, you'd also need to replicate the directory structure of e.g. the 'ImapMail' directory. So I'd not recommend doing it this way, you're likely to end up with more work and time to get it right. And you'd still have a prefs.js file with a lot of dead wood in there.

Even though this article is slightly outdated, it should help to determine what to carry over to the new profile. https://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Thunderbird

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What are you trying to achieve in the first place? What's wrong with copying the entire profile directory?

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christ1 said

What are you trying to achieve in the first place? What's wrong with copying the entire profile directory?

I've been using this user profile for a long time, across various systems and Thunderbird versions. It's gathered a lot of cruft over this time and I've noticed I keep having to repair folders, so I would like to refresh the account.

I could create a fresh user profile and manually set the extensions/bookmarks/preferences up again, but if possible I would like to copy across the minimal config details and let Thunderbird handle everything else. This would also make backups simpler to handle (and smaller, but the vast majority of the size is `ImapMail/` and I already know I can ditch that).

Modified by Ben

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Chosen Solution

I could create a fresh user profile and manually set the extensions/bookmarks/preferences up again,

While this is a real pain, it's what I'd do though.

if possible I would like to copy across the minimal config details and let Firefox handle everything else.

I don't think it's that simple. Basically the entire configuration is in the file prefs.js. But it's not enough to just copy over the file, you'd also need to replicate the directory structure of e.g. the 'ImapMail' directory. So I'd not recommend doing it this way, you're likely to end up with more work and time to get it right. And you'd still have a prefs.js file with a lot of dead wood in there.

Even though this article is slightly outdated, it should help to determine what to carry over to the new profile. https://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Thunderbird

Modified by christ1

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christ1 said

Even though this article is slightly outdated, it should help to determine what to carry over to the new profile. https://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Thunderbird

That's looks like exactly what I'm after, thanks!