Impossible to change the type of programmer

Hello Arduinians,

Some time ago I upgraded the Arduino IDE from 1.0.5. to 1.5.5. r2 and then everything became wrong. Meanwhile I took all the time I need to figure out what is wrong but no chance.

Here is my working stuff: My OS: Windows Vista SP2 My Arduino boards: Pro Mini 5V/16MHz (ATmega 328P) and some custom made with ATtiny45 My programmer: USBasp My Arduino IDE: 1.0.5

After the upgrade to 1.5.5 r2 (and possible some other stupidities) I just figure out that, whatever I do use as programmer, the avrdude command was for STK500 with the use of a nonexistent com port but only for Pro Mini; for ATtiny45 everything is just fine.

I removed the 1.5.5 and downgraded to 1.0.5 which worked just fine before the upgrade. I remove all traces (I was able to find) as being Arduino (even in registry), I removed Atmel Studio 6.1 with the plug-in for Arduino.

[I din not yet re-install the Vista.]

This is what I get as command line for avrdude: with Pro Mini

C:\Program Files\Arduino\hardware/tools/avr/bin/avrdude -CC:\Program Files\Arduino\hardware/tools/avr/etc/avrdude.conf -v -v -v -v -patmega328p -carduino -P\\.\COM4 -b57600 -D -Uflash:w:C:\Users\GOGUNE~1\AppData\Local\Temp\build5503532959940097103.tmp\Blink.cpp.hex:i

with ATtiny:

C:\Program Files\Arduino\hardware/tools/avr/bin/avrdude -CC:\Program Files\Arduino\hardware/tools/avr/etc/avrdude.conf -v -v -v -v -pattiny45 -cusbasp -Pusb -Uflash:w:C:\Users\GOGUNE~1\AppData\Local\Temp\build5503532959940097103.tmp\Blink.cpp.hex:i

The program used for test is Blink.ino

I tried some other boards (from the menu list): the same error (STK500 and not USBasp) I tried other programmers (from the menu list): the same thing. Everything is well only with the ATtiny45.

One more thing: if I take (copy-paste) the good command and use avrdude manually everything is OK (the Pro Mini takes the program)

Thank you for the patience to read all this.

Any idea?

Thank you a lot!