Pololu Orangutan USB - Manual (Page 24)

2. Close any programmer serial port connections
Close any existing COM port connections you have that might interfere with the upgrading process. For example,
if you have AVR Studio open, make sure the AVRISP programming window is closed as this window ties up the
COM port your programmer is using.
Pololu Orangutan USB Programmer User's Guide © 2001–2011 Pololu Corporation
8. Updating Your Programmer's Firmware Page 24 of 32