Bitcoin Core cannot obtain lock I downloaded Bitcoin Core (64 bit) and I am still waiting for it to synchronize. But just now, when I open the software, it loads from 1% to 100% and then a message appears with the inscription 


  Cannot obtain a lock on data directory C:/Users/ADMIN/AppData/Roaming/Bitcoin. Bitcoin Core is probably already running.


Then the program disappears to the task bar and I can't open it from the task bar. Please, any help?
Try opening your data directory and deleting the file .lock

Make sure Bitcoin is closed while you're doing this.