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Class Not Registered error

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  • Igcine ukuphendulwa ngu lubbersk

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Hi, I am attempting to follow the various posts/videos to migrate my Thunderbird account to a new PC. This is necessary as my old PC is having hard drive problems and keeps crashing. I tried 1 suggested simple fix of just shutting down my explorer from the task manager but I still got the class not registered error. Unfortunately I believe the faulty hard drive is the reason I am getting a class not registered error when I try and open my profile folder (at least from 1 post I read). Thunderbird has also been crashing, again likely because of the hard drive. Anyway I can work around this problem?

Hi, I am attempting to follow the various posts/videos to migrate my Thunderbird account to a new PC. This is necessary as my old PC is having hard drive problems and keeps crashing. I tried 1 suggested simple fix of just shutting down my explorer from the task manager but I still got the class not registered error. Unfortunately I believe the faulty hard drive is the reason I am getting a class not registered error when I try and open my profile folder (at least from 1 post I read). Thunderbird has also been crashing, again likely because of the hard drive. Anyway I can work around this problem?

Isisombululo esikhethiwe

re :When I run Thunderbird on my new computer am I running it without setting up my email profile?

yes - you are not actually setting up anything just yet. Download and install and it should auto run first time and auto create a profile and ask to create a mail account. At this point you do not create/add any mail account, just Exit Thunderbird. Access Profile. Delete the auto created 'Thunderbird' folder and in it's place paste in the copied Thunderbird folder, then restart Thunderbird.

Funda le mpendulo ngokuhambisana nalesi sihloko 👍 1

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On old computer Make a note of what version of Thunderbird you are currently using because you need to use the same version on the new computer.

Exit Thunderbird. It must not be running.

Assuming your thunderbird profile is still in default location: Access: C:\Users\<Windows user name>\AppData\Roaming folder Right click on 'Thunderbird' folder and select 'Copy' then paste this 'Thunderbird' folder to an external hardrive so you can copy over to new computer.


On new Computer: Download and install exactly the same version as being used on old computer. If you are not using the most up to date version, then tell me which version and I'll tell you how to get that particular version. Run Thunderbird for first time - then Exit Thunderbird.

Now access: Access: C:\Users\<Windows user name>\AppData\Roaming folder It will contain a 'Thunderbird ' folder - delete that 'Thunderbird' folder. Now paste the copied 'Thunderbird' folder - into the 'Roaming' folder. So that it now has all the old data.

Start Thunderbird.

Okulungisiwe ngu Toad-Hall

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Hi Toad-Hall, Thanks for your response. It seems straight forward enough but I do have 1 question. When I run Thunderbird on my new computer am I running it without setting up my email profile? I did read that if you are migrating from a previous Thunderbird account that you don't want to set up an email profile on the new Thunderbird account. Or maybe since you are deleting the Thunderbird folder in the new account, it doesn't matter?

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Isisombululo Esikhethiwe

re :When I run Thunderbird on my new computer am I running it without setting up my email profile?

yes - you are not actually setting up anything just yet. Download and install and it should auto run first time and auto create a profile and ask to create a mail account. At this point you do not create/add any mail account, just Exit Thunderbird. Access Profile. Delete the auto created 'Thunderbird' folder and in it's place paste in the copied Thunderbird folder, then restart Thunderbird.

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Thank you so very much! This worked perfectly and my profile/emails are all there on my new computer. Even sent a test email and it is picking up the new ones. Hurray!