Programmer not responding

I'm getting a "programmer not responding" message. I compiled a sketch and uploaded it to the board. It worked fine. I modified the sketch, compiled it and tried to upload. Got the error message. Tried several times more and tried a couple of other sketches - same message. Pin 13 led blinks three times after reset is pushed so that seems to be OK. Any suggestions? Graybeard

which arduino board are you using? PC/mac? software version?

I"m using a Modern devices board on a Mac. Graybeard

2nd part of question. Mac OS is 10.4.11. Arduino is 0010. Graybeard

It looks as if the problem is solved. The reset button may be defective. Another button on the 5V out with a jumper to the ground has given me reset capability. I downloaded a couple of sketches successfully. It doesn't appear that I'm frying any components. Thanks for helping. Graybeard

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