Sounds like a script trigger has been set on the field that attempts to perform a script that has since been deleted. Right click the field while in Layout Mode and select script triggers. You can disable the trigger just by clearing the check box.
If there is supposed to be a script trigger in place here, take a look at it and see if it performs a sub script that has been deleted.
hmmm... a bit late reply, but I solved it with this method : goto Layout Setup > Script Triggers Tab, to remove the script :)