By default Steam bind "i" key to take Screen Shots. This key is also used in Darkfall to bring up Roles overview. Also you will type i multiple times in chat as "i" is an English Vowel.
There are multiple ways to fix this.
1) Exit out of Darkfall
2) Open Steam
3) Go to Steam Settings
4) Choose In-Game
5) You can either "uncheck" Steam Overlay or Change Screenshot shortcut keys to something Darkfall doesn't use. For example "ctrl+\"
6) Restart your computer. (Restarting Steam will also work)
Special thanks to a player for sending me these screen shots and instructions.