Hi BigSchnitzel,
Order Send Error 131 is due to an invalid trade volume being specified when attempting to open a trade.
You should use the FXT Editor to check out the Lot size, lot step, min and max lot variables to make sure something sensible has been exported.
Either that, or you can place the following code in your EA:
Print(MarketInfo(Symbol(), MODE_LOTSIZE));
Print(MarketInfo(Symbol(), MODE_LOTSTEP));
Print(MarketInfo(Symbol(), MODE_MINLOT));
Print(MarketInfo(Symbol(), MODE_MAXLOT));
Once you have done this, you will need to make sure your EA is doing the necessary “normalisation” of the volume prior to opening a trade.
Google also provides a wealth of information on this particular error which hopefully should assist.
Regards.
