This is a TT issue. After trying all the above recommendations, I just went in and put in a non existent user ID and password for my Schwab login, and it came back as not valid. Then I put in my correct user ID and password and it worked. If you have used TT before, I have a feeling it has a glitch in the system when it has you log into intuit that doesn't allow it to work as it should. However, by putting in a non existent user ID and password, this seems to clear it out and let you log in as you should.
I hope this helps.
