I'm assuming you have installed the same version of Thunderbird on new computer as is currently running on old computer. This is important.

You will need to start Thunderbird once on new computer so it creates a default profile. But do not create any mail accounts. This just ensures all the default folders are in correct location making it easier to locate.

On Old computer:

• Start Thunderbird
• Menu icon > Help > More TRoubleshooting Information
• Under 'Application Basics' half way down -Profile Folders - click on 'Open Finder'

A new window opens showing you the contents of your current 'profile name' folder.

• Exit Thunderbird now - this is important.

Profile folders are located here:

• ~/Library/Thunderbird/Profiles/<Profile name>/

At the moment you are looking at the contents of <profile name> folder

• You need to go up the directory - up to 'Profiles' folder, then up to 'Thunderbird' folder and finally up to the 'Library'
• Now copy the 'Thunderbird' folder to an external device.

On New computer:

• Start Thunderbird
• Menu icon > Help > More TRoubleshooting Information
• Under 'Application Basics' half way down -Profile Folders - click on 'Open Finder'

A new window opens showing you the contents of your current new 'profile name' folder.

• Exit Thunderbird now - this is important.

Profile folders are located here:

• ~/Library/Thunderbird/Profiles/<Profile name>/

At the moment you are looking at the contents of the new <profile name> folder

• You need to go up the directory - up to 'Profiles' folder, then up to 'Thunderbird' folder and finally up to the 'Library'

This time delete the 'Thunderbird' folder

• Then paste the copied 'Thunderbird' folder from external device into the 'Library' - in effect replacing the new default 'Thunderbird' with the 'Thunderbird' you have been using on old computer.

Start Thunderbird.

Thank you for the reply and modified instruction. However, after several attempts I am not able to make this work. Do you have any other ideas? Thanks in advance. Bob

If you followed those instructions then you are using an identical copy. There is no other way to get an identical copy.

However, on new computer, check the Firewall which may be the default supplied with computer or controlled by your Anti-Virus product. In the Firewall, Thunderbird must be set up as an allowed program otherwise the Firewall will block all access to the internet.

• Exit Thunderbird
• Access Firewall and set up Thunderbird as an allowed program.

I checked the firewall and it is turned off. Same for ant-virus software. After following the instructions above for importing the Thunderbird files from my old computer, all of the files seem to be in place on the new computer. When I launch Thunderbird it does not launch with the transferred email profiles. It launched like new software and asks me to create a user profile.

Am I missing a command for importing or viewing the imported files? Could it be a read-write permissions issue for the imported profiles?

Thanks for your continued help and support.

Update - I found the import files button and all is well. Thank you so much for your help with this. If I may offer a suggestion?

Update the help pages with the most recent instruction from Toad-Hall and add that you need to use the import button to bring the files into the new software installation. Some of us out here in user land land are slow on the uptake for what should be obvious.

Again - Thank you so much for your assistance.

Thanks to bmack1 for pointing out the Import button. I sure wish someone would give me a workflow for it. I've tried a number of ways to move Thunderbird but it has lost all my sub-folders and thousands of files. Here's my setup Current Macbook Air - High Sierra, Thunderbird 102.9.1 I want to move Thunderbird to: Macbook Pro - High Sierra, Thunderbird 102.9.1

I have tried this https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer Which made Thunderbird behave as a new installation. Useless. As I mentioned the Import button kind-of worked but really didn't. I'm open to suggestions or a real workflow on how to do this. Howard

Thanks to bmack1 for pointing out the Import button. I sure wish someone would give me a workflow for it. I've tried a number of ways to move Thunderbird but it has lost all my sub-folders and thousands of files. Here's my setup Current Macbook Air - High Sierra, Thunderbird 102.9.1 I want to move Thunderbird to: Macbook Pro - High Sierra, Thunderbird 102.9.1 I have tried this https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer Which made Thunderbird behave as a new installation. Useless. As I mentioned the Import button kind-of worked but really didn't. I'm open to suggestions or a real workflow on how to do this. Howard

If Thunderbird acted like you had a new installation then it sounds like: Either you did not Exit Thunderbird first before copying and/or before pasting. OR you did not copy the entire ~/Library/Thunderbird/ folder from Macbook Air and then on Macbook Pro - delete the new ~/Library/Thunderbird/ folder and paste in the copied 'Thunderbird' folder.

It is more complicated to just import profiles, so copy the entire Thunderbird folder. Follow the instructions I gave in my earlier first comment.

Thank you Toad-Hall. Yes I was sure to get ~/Library/Thunderbird transferred over, but then starting Thunderbird on the MB Pro, still gave me what looked like a fresh install.

I tried the export-import way and it worked much better; however, it didn't transfer a lot of emails and folders. So then I just exported the MB Air folders it missed, one-at-a-time, moved them to the MB Pro and imported them. Took me about an hour or so, but now I know I have everything.

With luck I'll never have to do this again, but still, a workflow showing how to use the export/import might be useful to others. Thanks again