Use Revo Uninstaller and remove the 2.9+ version completely, download the 3.xxx beta version and try again.
I had the same problem before (on Win XP), and on tbs forum, the owner BS'ed me with some crap answer, saying my PC had some communications problem with the server. It was TBS 2.9 version that was giving the error after an update (regular updates, which are always more buggier than earlier ones).
But at the same time, I also had TBS beta 3.xxx version installed and it was "communicating" with the server quite smoothly. So it was only BS that the creator gave me as an answer.
What I did then was, I removed both the TBS versions completely using Revo Uninstaller and reinstalled both again (without rebooting the PC). After that both versions worked and I never got that error again (well, until the next 3.xxx version update that is, and then there were more errors).
At that time, I had stopped using the 2.9xxx latest version, and didn't wanted to use that version again because the modifications in 3.xxx were better than the 2.9xxx.
Revo had removed ALL instances of TBS from the disk and registry so there were no conflicts which caused TBS to fail after an auto upgrade, so TBS worked flawlessly but the next auto upgrade saw the error returning.
The error is there because the upgrades do not over-write some of the earlier existing files in TBS folder and may be isn't correctly updating the registry also. Clearly it's the coding errors committed by the TBS coder/s which are causing so many head-aches to the users, but he/they will never recognize that fact.
P.S.: as you have only a fresh TBS installed, I'd suggest you to use the Beta 3.xxx version as the version 2.9xxx is an old version still being used because the 3.xxx is still in Beta. Possibly, the 2.9xxx has many compatibility issues -- your PC configuration in particular, the backend codes, the .Net compatibility, and others.