Oh, one last question, I upgraded because one of my email providers needed Oauth2 to access.

Upon research, it seems T-Bird added that feature around V60 or 70.

When did they change from .mab to sqlite?

Is there an older version I can download that use the old mab files, yet the new Oauth2 login?

Thanks, Mark.

1. Synced file system locations are not supported. They cause far more issues than they solve, including data duplication and loss.

2. The address book format changed with V78. when mozstorage was adopted to replace the mork file format as there are moves to fully remove all mork databases from the platform, along with XUL. mozstorage is based on sqlite.

3. Why not just use an ldif or carddav server implementation and share your address books that way, either by hosting your own instance or using one of the free providers like GMX or Google. The latest version (91) of Thunderbird can locate your address book with oauth providers and your calendars and simply ask you if you want to use them in Thunderbird.

4. Old versions as you have already noted simply do not work with newer implementations of things like oAuth, and despite it all having the same name, each provider keeps up a constant change. The Google oAuth implementation for instance has had to be patched multiple times in recent years and the outlook one is still a work in progress.

So to your questions.

2) Am I safe to upgrade the other 2 computers to V91, then create links to all the new file names? I guess there will be 24 links I need to create now. Eight wasn't enough.

I suggest you rethink you synchronization process. it is not really supported and as you have found suddenly stops working because it is not a supported method of doing things.

Why the hell was it necessary to go through all these hoops to simply share an address book across computers?

It is not, I use my Google and GMX adress books from the web on each device including my phone.

Why can't I tell T-Bird where my address books are located, and why did they force me to place them in my profile folder?

Personally I would like to see less allowable configuration of storage locations not more. But then I do support where people who know just enough to get into trouble go when they mess it up.

Your Thunderbird data belongs in your profile, not scatted in a collection of random locations that make locating what you have where difficult. The profile import and export is greatly complicated by these out of profile stores and anti virus program that might respect the Thunderbird profile do not do so when the data is elsewhere, so scanning results in locked files and data corruption. Lots of reason really, and none really for placing the address book outside the profile. Not when synchronization via the network is available.

What advantages does it serve to go from a .mab file to a .sqlite file? (I assume the reason for this was to use a different database manager for the address books? Seems to me the old one worked just fine.)

Well it was not just fine. The address book is in the process of a complete re write. The changes are far from over and as a decision was made to remove MORK, the MAB files had to go. MSF files are next I think

Why call them abook-1 and abook-2, not simply use the name the user call's it when he creates it?

For one we don't want you touching the files outside of the application, for another we inherited the convention from Netscape. That is how old this stuff that is being updated really is.

Hi Matt:

Thanks for the verbose response, and thanks for not taking offense at my obvious tone of frustration that probably should have been softened a bit.

I was going through these hoops because I don't want my contacts stored on the cloud. As a company, I'm sure Google wants to be secure, but the people that work there are human and some of them may be willing to sell people's stuff to bad actors to make a buck.

But, then I realized I have many of my contacts stored and synced on my phone anyway, so I figured if I am going to use a phone, I might as well just drink the cool-aid and go all in. Sigh.

So, I am going to start a new thread asking for better instructions to do this.

Thanks for your help, Mark.

You can always run your own LDAP or CARDDav server on a local NAS and do your syncing to that.

More hardware and more asked of you to administer, but you don't have to drink the cool aid. That part is your choice. But in the end, I find I am being forced to add contacts to address books in the cloud just to stop the providers marking mail as spam anyway.

With Thunderbird 91, the best is to use one of the oAuth providers like Google, GMX and yahoo and allow Thunderbird to detect the address book and set up the synchronization natively.

Thanks, Matt:

I get the "add contacts to cloud book to stop the provider flagging as spam" thing. What a PITA, but whattayagonnado.

I have experimented with adding my Google contacts, (without TbSync) and I now have a new contacts list and it seems to be working.

Now that I have had that cookie, I want the glass of milk too.

I have 8 other lists (address books?) in T-bird, like "Friends", "Frequent", "Family", "Pests", and others. This makes finding my brother easier then searching through the entire list.

I know Google has "Labels" but they don't seem to work like T-Bird folders.

Is there any way I can sub divide the Google list in T-Bird?

Ideally, I'd like to keep the format I am used to with separate lists, but I would be OK with sub folders in the google list.

I had the idea of keeping different accounts for the different lists, (friends in one Gmail account Family in another, pests in my Microsoft account, etc...) but that means telling my phone about all my accounts, and I'd rather not do that.

Thanks, Mark.

I limit my Google contacts, so am not experienced there with more than a bare minimum, but I think you might want to try out the card book add-on

https://addons.thunderbird.net/en-us/thunderbird/addon/cardbook/

If my failing memory servers, It managed to provide me with contacts by label from Google. But I have tried so many addons doing that stuff they all tend to be run together these days.