Answer to: Canon 60D won't turn on?Hi, I just had this happen to me. I'd just started using a new lens (50mm 1.8 STM) and tried different combinations of lenses, etc. Both batteries I tested were full or near full. Long story short: it turned out to be caused by the micro-SD card in a Transcend SD adapter! Once I'd taken that out and removed / replaced the battery, everything worked as before. Really, really weird.