Looks like TDA decided the best time to do a forced software update was at the Monday morning NYC open. Try to close the platform and see if an update runs for you. It is quite long unfortunately. It updated over the weekend as well, so perhaps they had to correct an error created by the weekend update. ToS is an excellent platform for charting and options trading. But for futures, TDA is not the place to trade.
I tried that to no avail. Everything was fine this morning until the open. Lucky I was not in any trades.
That is when it seems to have gone down for everyone. Even the update is locking up at loading index file. TDA's ToS may be the victim of a DoS attack. I had to move programs to IB that I usually trade at TDA.