If you haven't deleted profiles, the addressbook is somewhere. Name is abook.sqlite in case do a full search. Normally, the proflles used will be at c:\users\<yourid>\appdata\roaming\thunderbird\profiles. There may be multiple profiles there, and likely an abook.sqlite in each, so look for the one with latest update date. Also, look for history.sqlite for the collected address folder. Once you find it, you can copy into your active profile when thunderbird is not running, or use the tools>import>import a file option..

Hi David, I'm sorry I haven't responded to your ' solution ' , but I didn't get an email notification of it and support forums aren't somewhere I normally spend much time on as I don't understand most of the stuff that's posted as it seems to me I'd need a degree in computer science . I've just read your repsonse, and although I appreciate your time and effort but, it might as well have been written in Mandarin! I've tried searching for: abook.sqlite c:\users\<yourid>\appdata\roaming\thunderbird\profiles. with what I presume is my ID

Every attempt results in the message " No items match your search " apart from one which led to this result:

[Install8216C80C92C4E828] Default=Profiles/hxffq3wk.default

[InstallD78BF5DD33499EC2] Default=Profiles/xgkctjvv.default-release Locked=1

[Profile1] Name=default-release IsRelative=1 Path=Profiles/xgkctjvv.default-release

[Profile0] Name=default IsRelative=1 Path=Profiles/hxffq3wk.default Default=1

[General] StartWithLastProfile=1 Version=2 As I said, it might as well have been in Mandarin!

I'll say the same as I've just reposted: " Hi,

I'd like to know why my address books have disappeared after downgrading from 115 to version 102.15.1. 

Like many others it seems I really didn't/don't like 115 at all, so after a lot of faffing about I've managed to change it back to 102.15.1 (64bit ). Now it looks better, familiar and more intuitive but, my address books have disappeared, both collected and personal. Now if I want to send an email I have to look up the complete email address ( if I can find it ! ) rather than just entering the first one or two letters. Any help with this problem will be very much appreciated, as long as it's in easy to understand English and not in computer geek speak which I'd need a degree in computer science to understand!

I also looked at the tools>import>import a file option butb gave up at " Import Address Book file " as I have no idea what the diferent files mean.

Thanks Alf J

Your search found the addressbook in two profiles, one named hxffq3wk.default and one named xgkctvv.default-release. Assuming Windows, the full path is something such as this: c:\users\<yourid>\appdata\roaming\thunderbird\profiles\<a profile name> . Since thunderbird puts a default (empty) addressbook in profiles, my guess is one of those is the empty one and the other is your addressbook. Are you somewhat comfortable with Windows File Explorer? A bit of knowledge will help. Anyway, I'll try to simplify it a bit if I can. Do this:

1. in thunderbird, click help>troubleshootinginformation
2. scroll down left side to 'profile folder' and click 'open folder'
3. now exit thunderbird.. you are now in the profile. Notice the name of the profile. Is it one of the two from your search? Do you see an abook.sqlite file? If so, note date of last update and its size.
4. now, click back to prior folder, which will be the folder name 'profiles' . it should list your profile and any others, and I expect you to see the other profile listed there. click to enter the other profile folder. note its abook.sqlite file and date of last update and size. Is it bigger than the one in other profile? if so, it's likely your missing addressbook. Note the physical location. Windows file explorer wil be displaying the file name and location in upper area of screen.
5. at this point, you know location and size and date of last update for each and (I hope) have determined which is your addressbook.
6. ok, pause, pour a glass of scotch, eat a few peanuts and we'll continue.. :)
7. restart thunderbird
8. click tools>import>import from a file
9. click the addressbook option and then click the sqlite option, and then locate and select the abook.sqlite you had determined to be your addressbook and click ok.
10. now, click the addressbook icon on spaces toolbar or however you access addressbook and verify that it has desired content.
11. if all is well, it's time to pour another ounce or two to celebrate
12. FINALLY, I suggest doing this:
    • exit thunderbird - IMPORTANT
    • copy c:\users\<yourid>\appdata\roaming\thunderbird to external media this is a BACKUP
13. if you ever need to restore from a download or crash or god-knows-what, you can install thunderbird and then exit, and then copy the backed-up thunderbird folder to c:\users\<yourid>\appdata\roaming to overlay the existing thunderbird file and you'lll be done.