Is it because of windows 10?
If your Arduino IDE screen is grey then try this:
- Select File > Preferences from the Arduino IDE menus.
- Uncheck the checkbox next to "🗹 Use external editor".
- Click the OK button.
This "Use external editor" feature is for people who prefer to use a different text editor than the one built in to the Arduino IDE for writing their sketches, while still using the Arduino IDE for compiling/uploading/installing libraries/etc. So it disables the Arduino IDE's built-in editor to prevent confusion or lost work that might occur if you forgot and tried to edit and save the sketch from both editors.
You can try uninstalling the arduino ide and installing it afresh.
It is not because of windows 10. I also upgraded to windows 10 but it is working just as before.
Thank you ALL.