Installed 1.6.0 the system worked fine. Up graded to 1.6.1 no sketch

I am a new user. followed the Instructions and the system worked, power on and blinking light. I tried to up grade from 6.0 to 6,1 and the system made me uninstall 6.0. Had some problems downloading 6.1 but got a clean copy on the third try. I haven't seen my sketch pad since. This is a Arduino uno an ATmega 328p 1422.

Rob153