Are you playing TB2.5? Are you running it on Windows 7 or 10? Some people here seem to be okay running it with Windows 10. [I've got 2.5 on Windows 7]
I'm guessing you've already tried re-installing?
There's a couple of posts somewhere on here from Jersey Jim on a potential fix. I just can't recall where they are.
Try here:
https://forums.ootpdevelopments.com/...d.php?t=178455
If this works a moderator should sticky it.
Cap