Since the update pushed yesterday, it is impossible to launch backtests ! I'm currently getting "global initialization failed" and "global initialization critical error".
Not - no one reported ... it was some issue with something (it was discussed on rus thread) but it was because of the EA which had a bug.
So, the service desk may help - they may reply with fixing, or they may issue the new build with fix.But be ready to send log files to them and all the information (Windows version, and more).
You can simply copy the three files of a previous build over the current ones.
Every time you restart MT5, you must say "no" or "cancel" or whatever it is when they ask you to update.
If you didn't keep a copy around, here's MT5 build 1755 for 64 bit.
Thank you Anthony ! Yup everything works fine now, except my market watch disappeared with all of my custom symbols, and yet they are in C:\Users\USERNAME\AppData\Roaming\MetaQuotes\Terminal\XXXXXXXXXXXXXXXXXXXXXXXX\bases\Custom\history folder. Another problem to solve I guess, but in the meantime I can work and debug on the broker symbols.
Regarding the build 1816, just to clarify, my EA havily relies on pointer functions (delegates) and the new build completely messes this up. For instance, I have a StopLossSignal Class that needs a delegate for the desired exit price. I can give examples if you want further explanations.