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Migrating Thunderbird, Win 10 to Win 11

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  • Last reply by jeff236

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Hi.

I've recently set up a new computer. I'm a Thunderbird user.

My old computer is running Windows 10. My new one runs Windows 11. I'm running the same (current) version of TB on both computers.

I can't get my emails to move from one computer to another. I know, this sounds dumb, but it isn't; my email provider uses a weird hybrid of POP3 and IMAP, and just "connecting" didn't do the trick; in fact, adding my account to TB under 11 ate most of my emails on the server because the default TB/POP3 setting kills all old emails after 14 days.

Fortunately, my old emails still live on the Windows 10 computer because it DOESN'T do that.

I have tried export/import, but that doesn't work because my account is very old, very large, and creates a 5GB file. I've tried just MOVING it, but TB isn't picking up the old stuff correctly.

I'm pretty sure this is a TB 10/11 incompatibility for one simple reason: when I export just my address book from the 10 installation the import fails on the new (11) machine, BUT when I export it from another machine that's already running 11 I can import it on the new machine.

How do I export mail from TB on 10 and import on 11 ?

Thanks!

Hi. I've recently set up a new computer. I'm a Thunderbird user. My old computer is running Windows 10. My new one runs Windows 11. I'm running the same (current) version of TB on both computers. I can't get my emails to move from one computer to another. I know, this sounds dumb, but it isn't; my email provider uses a weird hybrid of POP3 and IMAP, and just "connecting" didn't do the trick; in fact, adding my account to TB under 11 ate most of my emails on the server because the default TB/POP3 setting kills all old emails after 14 days. Fortunately, my old emails still live on the Windows 10 computer because it DOESN'T do that. I have tried export/import, but that doesn't work because my account is very old, very large, and creates a 5GB file. I've tried just MOVING it, but TB isn't picking up the old stuff correctly. I'm pretty sure this is a TB 10/11 incompatibility for one simple reason: when I export just my address book from the 10 installation the import fails on the new (11) machine, BUT when I export it from another machine that's already running 11 I can import it on the new machine. How do I export mail from TB on 10 and import on 11 ? Thanks!

Chosen solution

Thanks, David. Success!

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Here is my approach: - exit TB on old computer (it is important that TB NOT run during the copy) - copy c:\users\<yourid>\appdata\roaming\thunderbird to a USB stick - on new PC, install Thunderbird if not already done. - exit TB on new computer - copy the USB thunderbird folder to c:\users\<yourid>\appdata\roaming\thunderbird (you will be prompted for overwrites. Allow to proceed) - start Thunderbird

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Chosen Solution

Thanks, David. Success!