For about 8-10 days, the quote freeze problem seemed to have disappeared. Yesterday, at about 12:15 EST and today at 14:03, the TWS futures quotes froze again. As before, a complete exit and restart is required to get things going again. For years, TWS did never behave like this. This problem appears to have started at about the time IB introduced the backfill feature, IMHO perfectly useless for most traders. Anybody else encountering similar incidents? PS: went back to the older build 826.4, but the problem seems to occur with all builds. I don't use front ends. I am only using an Activex-API based VB6 application that ran for 24 months now without any trouble. No modifications and no other activity on the same computer as before.