Since your USB ports likely work for other things (like your keyboard) and you have tried several arduinos, cables etc, now try Knoppix - it has both Arduino IDE (not the most recent version) and avrdude. https://unetbootin.github.io or https://www.pendrivelinux.com/install-knoppix-6-to-a-usb-flash-drive-in-windows and http://www.knopper.net/knoppix-mirrors/index-en.html

If it does not work, have a look through the boot log, or more quickly dmesg after plugging your arduino in and trying an upload.

Worth noting: the 328p target is not correct for mega, use e.g.: avrdude -vv -p atmega2560 -b115200 -c wiring -P COM3

If you still get errors, and have not fiddled with clockspeed or anything else, it will be very strange indeed.

Since your USB ports likely work for other things (like your keyboard) and you have tried several arduinos, cables etc, now try Knoppix - it has both Arduino IDE (not the most recent version) and avrdude. https://unetbootin.github.io or https://www.pendrivelinux.com/install-knoppix-6-to-a-usb-flash-drive-in-windows and http://www.knopper.net/knoppix-mirrors/index-en.html

If it does not work, have a look through the boot log, or more quickly dmesg after plugging your arduino in and trying an upload.

Worth noting: the 328p target is not correct for mega, use e.g.: avrdude -vv -p atmega2560 -b115200 -c wiring -P COM3 or avrdude -vv -p atmega2560 -c wiring -P /dev/ttyUSB0. Omitting -b115200 should be no problem with the mega. Try this before torturing yourself further...

If you still get errors, and have not fiddled with clockspeed or anything else, it will be very strange indeed.

Since your USB ports likely work for other things (like your keyboard) and you have tried several arduinos, cables etc, now try Knoppix - it has both Arduino IDE (not the most recent version) and avrdude. https://unetbootin.github.io or https://www.pendrivelinux.com/install-knoppix-6-to-a-usb-flash-drive-in-windows and http://www.knopper.net/knoppix-mirrors/index-en.html

If it does not work, have a look through the boot log, or more quickly dmesg after plugging your arduino in and trying an upload.

Since your USB ports likely work for other things (like your keyboard) and you have tried several arduinos, cables etc, now try Knoppix - it has both Arduino IDE (not the most recent version) and avrdude. https://unetbootin.github.io or https://www.pendrivelinux.com/install-knoppix-6-to-a-usb-flash-drive-in-windows and http://www.knopper.net/knoppix-mirrors/index-en.html

If it does not work, have a look through the boot log, or more quickly dmesg after plugging your arduino in and trying an upload.

Worth noting: the 328p target is not correct for mega, use e.g.: avrdude -vv -p atmega2560 -b115200 -c wiring -P COM3

If you still get errors, and have not fiddled with clockspeed or anything else, it will be very strange indeed.