I am working on avr controllers for a while, but I have problem with "progisp" avr programming software. When I buy a new micro-controller like atmega32 it can be programmed properly for a while but after some days, suddenly when I want to reprogram it, Progisp shows the error "Chip Enable Program Error". I use USB programmer. For better understanding here is an image of progisp software.
I have searched the internet a lot to find a solution but there wasn't a proper and useful solution for my problem. I am sure that my micro-controllers are fine and not damaged because they work as they programmed but I am unable to reprogram them. I really thank you if you have any solution to help me.
And here is schematic diagram and real picture of my USB programmer.