when I click "download", there will be a window like the picture, should I click "OK" or "cancel" ?
If you click "OK" the terminal will download historical rates from MetaQuotes History Center. This history may be differ from history of your broker. Make backup and try, it is difficult for me to say exactly.
I have looked for the old post in this forum,and I know it's because of the discorrespond of different timeframe's data. I saw someone say "Synchronize your data! ",but how to?
I see most of the "unmatched data error" are relative to the "volume", but in foreign exchange trade,volume is no use, so is there any way to clean all the volume of the history data?