When Co:Writer Universal is installed on the device the Prediction Language is set to US by default. On the Co:Writer Universal options page if any account using the device changes the Prediction Language, when the device is restarted then Co:Writer Universal on that device is set to that language. When you log into Co:Writer on a device that has the Prediction Language set to one that is different then your Co:Writer setting, you get the Language Changed message.
Steps to change Predication Language back to US:
1. Have the user who needs to change their Predication language login to the Co:Writer Extension.
2. Left click on Co:Writer icon on the Chrome Tool Bar.
3. Click on prediction Language
4. Click on English (United States)
5. Wait for the Language and Extension to reload.
Once Co:Writer has reloaded refresh the web tab you are using Co:Writer on and continue typing.