BaseCamp may display the error "There was a problem communicating with the Garmin device" if corrupt data is encountered on a connected device.
Corrupted files that may cause this issue include the following file types:
GPX (Waypoints, Tracks and/or Geocaches)
JNX (Birdseye files)
JPG (Pictures)
You need the corrupted file from the internal storage using Garmin BaseCamp.