I've had an account with IB for a number of years, and this is only the second time I'm having a problem with them. However, it is troubling, because I ended up with an extra fill. Which could've been a disaster, but I got out for a small loss the next day. I think the problem occured that ScaleTrader did not shut down correctly after I cancelled the scale orders. It executed one another trade several minutes after. I never saw that extra position in TWS - until the end-of-day statement came. Has this happened to anybody else? Should I refrain from using ScaleTrader? IB customer service was quick to reconcile the positions, to their credit. But I was never able to get any technical help from IB over the years - it's take it or leave it.