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Is the thunderbird address book stored locally?

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Hi there,

I recently reformatted my computer and reinstalled windows 10. I reinstalled Thunderbird thinking that the address book/contacts were stored online on Mozilla's side, so once I readd my emails accounts, they'd be restored. However, my address book is empty, and when I start typing an email address in the "To:", thunderbird isn't autofilling or suggesting contacts. Am I right in assuming that the address/book contacts were actually stored locally on my computer and not online, so reinstalling windows 10 erased it? Or is this a bug?

Thank you

Hi there, I recently reformatted my computer and reinstalled windows 10. I reinstalled Thunderbird thinking that the address book/contacts were stored online on Mozilla's side, so once I readd my emails accounts, they'd be restored. However, my address book is empty, and when I start typing an email address in the "To:", thunderbird isn't autofilling or suggesting contacts. Am I right in assuming that the address/book contacts were actually stored locally on my computer and not online, so reinstalling windows 10 erased it? Or is this a bug? Thank you

Modified by jeffjeffjeff

Chosen solution

Nope, address books are stored in your profile, on your machine. Mozilla has no involvement with your data; they (or a department of them) just wrote the software you're using. No servers, no email accounts, no online data storage.

https://support.mozilla.org/en-US/kb/profiles-tb

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All Replies (4)

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Where exactly do you think the "Mozilla Side" is?

You formatted your computer and the normal meaning of that is to wipe the local drive and all it's contents. That would include your Thunderbird profile and all it's contents. Including the address book.

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Chosen Solution

Nope, address books are stored in your profile, on your machine. Mozilla has no involvement with your data; they (or a department of them) just wrote the software you're using. No servers, no email accounts, no online data storage.

https://support.mozilla.org/en-US/kb/profiles-tb

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Thank you for the prompt replies. By Mozilla Side I meant maybe a server side? I apologize if this seems like a stupid question, I'm just trying to get a better understanding of how everything works.

Modified by jeffjeffjeff

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Thunderbird is email client software running on YOUR computer. There are no servers. Email providers have servers.