Hello! Arduino IDE stopped typing sketches. The cursor does not appear in the sketch edit box. Additional equipment is not set. Without connecting the board, the program also does not work. Reinstalled, did not help. Windows system7. Help me please 
You set the Arduino IDE to use an external editor. You can make it editable again by doing this:
- File > Preferences
- Uncheck the box next to "Use external editor".
- Click "OK".
Shannon, thanks a lot !!! Everything worked out!!!
You are a very good specialist!!!
You're welcome. I'm glad if I was able to be helpful. Enjoy!