Arduino uno doesn't store sketch when i turn off power

hi guys!

i have a problem with my uno r3 (original)

every time i disconnect the board from the power, it loss the sketch that i've uploaded

so every time i need to upload the same sketch in my board, before use it

someone can help me?

This might very well be just a shot in the dark.

Have a go at reloading the bootloader from the latest version of the IDE. Let me know if it makes any difference.

The sketch is stored in the Arduino's flash memory before it is run, so it cannot be lost. Try uploading the blink example, let it run, then disconnect and reconnect power. What happens?

thanks guys, problem solved

i just tried changing the programmer. i used USBtinyISP instead AVRISP ad it worked well