Harmony Remotes

[JKin]

I have an 1100 remote (recent purchase).  After a device update, it started sending out "4" characters in a stream spontaneously.  So, I attempted to re-update.  But device mgr didn't recognize.  I removed and returned battery.  Now screen is blank/black and device manager sees as "Unknown device".  At this point I'm stuck: I can't see screen to do anything on the device and I can't update the device as device manager won't recognize it.  Help appreciated.