I thought I read something about this in the past, but couldn't find the post. I thought I'd pass this along in case someone else runs into this.

We have various machines with TP 5.6 installed. Some have the patch of build 81 installed, some have older patches (build 75 was the most common).

Recently, I needed to run some tests using an older version of our product, which is a different DB. The DB itself was updated to TP 5.6 when TP was upgraded. Subsequent patches to TP 5.6 never said that the DB needed to be modified or upgraded...

So after running a few times on this database with these builds 75 and 81 of TP 5.6, all of a sudden one day, none of the non-build 81 patched machines will connect to the DB anymore. That is, all the build 75 version of TP crashed trying to load the db.

I did various tests, integrity checked the DB, the ODBC connection worked, etc... everything was fine. Then I remembered something I read in the post I cannot find... Something about patches causing data connection problems...

After upgrading them all to build 81, they worked.

I believe if you use a build 81 version of TP 5.6 and modify the DB in some way (cannot know exactly for sure what I did), older build of TP 5.6 will no longer work until they are upgraded.

Hope this helps someone.