Your data is still there, it just isn't being read by TB. Select Help/Troubleshooting Information, click about:profiles. Do you see other profiles besides the one in use? If you 'Launch in new browser' does your old data appear? If it does, set the correct profile as Default.

New Browser is "Release 1" the data from my old browser will not launch in the new browser.

Can I uninstall the Release 1 and re-install the latest Thunderbird program and still get all my data from the original profile??

What version of TB do you have, and it is 32-bit or 64-bit? Do you have more than one version installed, in Program Files (x86) for 32-bit or Program Files for 64-bit? What is listed in about:profiles?

Version 68.2.1 32 bit It says I am in a "Release Update Channel"

Profile: default-release-2 This is the profile in use and it cannot be deleted. Default Profile yes

If you open this location in File Explorer

C:\Users\<winusername\AppData\Roaming\Thunderbird\Profiles

(Enable hidden items in Explorer View tab.)

are there other profile folders beside one ending in default-release-2?

In the Thunderbird folder, open profiles.ini in a text editor and copy the contents in a reply here.

I have 5 profiles at this time: "default-beta" this was my original profile which contains all data "default" "default release" the upgraded profile "default release-1" I created in an effort to launch data "default release-2" I created in another effort to launch data. When trying to launch the older beta profile I get a message that says: The older version is not compatible with the newer version, so launch a new profile or exit. So I tried a new profile twice.

Can I uninstall the Thunderbird program without loosing any of my address books? Then I could reinstall whatever version is available, which is probably not a "release" version. Then maybe I can launch the old beta profile on the newly installed version.

The new version 68.2.1 does not support all the data that the beta version did. I have to have that data, so I guess I'll try to try to reinstall the beta version if I can find it. Then I can use that profile.

I think you can get TB 68 to read the default-beta profile by selecting it in Profile Manager. Windows key+R, type thunderbird.exe -p

If that doesn't work, add -allow-downgrade to the command line.

It's something of a mess with profiles created by beta and release versions, but with some work you should be able to recover your data in a working TB 68 profile.

https://support.mozilla.org/en-US/kb/unable-launch-older-version-profile

Ok with your help I recovered the old Beta Version of Thunderbird. all my data and emails to the point of upgrading to the new version is there. I would like to stay with that profile as I have marked it as default. However, it will not retrieve my new messages. I checked the incoming server data and it is correct. i.e. inbound.att.net port 995.

Do you have any idea how I can get incoming mail to that profile??

Any error message? AT&T has started requiring a 'secure mail key' in place of normal account passwords. Perhaps try deleting the password from Tools/Options/Security/Passwords/Saved Passwords, restarting TB, and entering the password or mail key when prompted.

No error messages. I removed all passwords Reloaded TB It opened in the default Beta Profile which contains all data No password prompt or required Password on att.net web email works perfect and all amails arrive Don't need a mail key

The emails will load into the new release default profile, but they will not load onto the beta profile

OK, I have followed the thread. I was able to load the former beta profile which contains all my address books and archived messages. However, it will not send and receive messages.

The TB 68 profile will send and receive messages but all my address books and archived messages did not migrate to the new profile, even though I hit "launch profile in new browser"  

So, can anyone tell me how to migrate my address and archive data to the new TB 68 program? OR tell me how to make my former beta program functional. (Activate inbound and outbound actions) The account shows proper selections titles and ports.