Hey Jeremy -
TabJolt works fine against 10.2 - Nothing to see there as far as I know. I've never seen that error message either, though. How are you providing URLs to TabJolt? Based on this error message it almost makes me think that you aren't using vizpool.csv (default) but instead are using the "web" approach (TabJolt connects to the PostgreSQL database and grabs viz names directly from Tableau).
I typically don't use the web method since my Server has some viz-cruft in it that wouldn't make sense to test and I like the fine-grained control of vizpool.
How are you actually providing credentials to TabJolt? Are you leveraging userpool.csv (I DON'T think that will work in web mode, but I've never tested it), or are you "hard coding" in ServerTestConfig? Make sure the admin user (in Tableau) is in the latter file.
I frankly wouldn't be totally surprised if "web" is sorta broken - it doesn't get used a lot, and therefore not as much love...
I have a very similar issue to Jeremy, but slightly different configuration. I'm running Tableau Server in AWS and we connect to it via https://. I installed Tabjolt on my local workstation and on the Tabjolt Configuration screen, I can't get past the first tab "Tableau Server Information". I get a message that the username/password aren't correct.
However, if I hit the same URL from my browser, with the same Admin credentials, I can get in just fine.
Thanks in advance,