New ida uploads sketch and Uno R3 just spits out on Tx

In the middle of troubleshooting a sketch for telescope focuser, I switched to the latest ida, 1.6.2. Now, once the sketch is uploaded the Tx light stays on, the serial monitor spits out ÿ and Þ characters, and the board does nothing else. The code which previously worked except for the glitch, plays dumb. I'll post the code if anyone wants it but there's nothing in it that even calls for the Serial monitor.

I heard that in v 1.6.2 still under development process. So kindly download v1.0.6

Have reverted to previous version of IDE. Problem gone.