As of early January 2017, it seems that Google AdWords is experiencing an error with its search term report.
“There was an error with your operation. If you were trying to make a change, it may not have saved. Please refresh this page to try again. If the error continues, log out of your AdWords account, then log in again and return to this page.”
The solution that I found was to remove “All Conv” conversion columns and use “Conversions” instead. Hopefully this will be fixed soon!