Duemilanove - avrdude error

After trying to upload a new sketch to my Duemilanove (328 chip), the board doesn't seem to be downloading it. I am getting an error message that says avrdude: stk500_getsync(): not in sync: resp=0xc0. Also, I am using Mac OS 10

After reading other posts, it seems to be an issue with the bootloader, but I'm not sure how to correct the problem.

Please help.

MOB

It looks like you should go through the full troubleshooting routine provided as a sticky article at the top of this forum.

Specifically, about this error, http://www.ladyada.net/learn/arduino/help.html states:

"Check the following:

If you have a NG Arduino, did you press reset just before selecting Upload menu item? Is the correct Serial Port selected? Is the correct driver installed? Is the chip inserted into the Arduino properly? (If you built your own arduino or have burned the bootloader on yourself) Does the chip have the correct bootloader on it? (If you built your own arduino or have burned the bootloader on yourself)

Note that it is nearly impossible for anyone to debug this, as there are so many possible issues. Try everything. "

Here is another line of error that I'm receiving: avrdude: ser_drain(): read error: Device not configured Does this help narrowing down the possible issues?