Do you happen to be from Germany?
If you are, the issue is with a keyboard incompatibility between German and English. German keyboards tend to insert commas instead of decimal points. To fix this problem:
- Go into Start (if you are a Windows user)
- Click Systemsteuerung, Regions
- Choose und Sprachoptionen, Regionale Einstellungen:English(USA)
From that point on you should have no problems.
Thank you to Rule #1 fan Michael from Germany for troubleshooting this problem!