Problem while programming for SCL in Main OB & FB

Hello Folks

I received an error whenever i start programming for SCL in both program section Main OB & FB, can't able to type 'IF' keyword initially and my software gets freeze and received an error message that i have to close the software deliberately. It seems like SCL isn't possible in my software. Can i get any solution for it ? I am using TIA portal V16

Thanks

Image may be NSFW.
Clik here to view.