I have the same problem, I'll post again if/when I figure out what's wrong.
You have to install something called EQ2Extreme.
http://gforge.xunleashed.com/gf/project/eq2extreme/frs/
http://www.taultunleashed.com/phpbb2/about51427_EQ_Extreme_with_Exhume____Check_for_updates_on_GForge.html
You also have to copy the harvestbot_v502.exe & HarvestBot_v502.ini files into the C:\Program Files\EQ2Extreme directory and run it from there.
Be sure to open the .ini file and follow the instructions in it.