Hi,

I tried to define new key in python idle and then python 2.5.1 failed to launch. 

What I did : I defined a new key, applied and changed my mind, removed my key set named 'ole'.

I launched cmd
C:\Python25\Lib\idlelib>..\..\python idle.py

got dozens of messages :

Warning: configHandler.py - IdleConf.GetOption -
problem retrieving configration option 'redo'
from section 'ole'.
returning default value: ''

Finally, this opened python idle so I went again to configure idle/keys and saw that my key set was still there. I selected again "Delete custom Key set" and now it's ok.