I made a video some time ago for one of my students and in it I explained how to go about testing your expert advisors. One of the things I mention in the video is the fact that due to the way Strategy Tester works, it's never to be trusted 100%
Now initially that may sound a bit shocking to you but it's really not that big a deal.
The Strategy Tester in MT4 isn't intended to give you a reliable representation of exactly how an expert advisor will perform in a live market. If you think about it for a moment the idea that it ever could is a bit ridiculous.
By it's very nature the live Forex market is unpredictable just like everything else in life that involves human interaction. (more…)