why does my space key always shows the letter 4 whenever i press the space button

This behavior is typically caused by a keyboard hardware issue or an incorrect keyboard/input configuration, not by Outlook itself.

Try these steps to isolate and resolve it:

1. Test with another app
   • Open another app on the device (for example, a notes app or browser) and type there.
   • If the space key still types 4 in other apps, the issue is with the keyboard or system input, not Outlook.
2. Check for debris or physical damage (hardware keyboard)
   • If using a physical keyboard, debris under keys can cause incorrect characters.
   • Gently clean the keyboard:
     • Use compressed air to blow under and around the spacebar and nearby keys.
     • Wipe the keys with a slightly damp microfiber cloth.
   • If possible, test with an external keyboard:
     • If an external keyboard works correctly, the original keyboard is likely faulty.
     • If the external keyboard shows the same issue, the problem is likely software/driver related.
3. Check keyboard/input settings (on the device)
   • Open the device’s keyboard or language/input settings.
   • Ensure the correct keyboard layout is selected (for example, the correct language and layout for the region).
   • If multiple keyboards are installed, switch to another layout and test again.
4. Restart and update
   • Restart the device.
   • Install any pending OS and keyboard/driver updates.
5. If the issue persists
   • If the space key still types 4 after cleaning, testing another keyboard, and checking layouts, the built-in keyboard is likely failing and may need repair or replacement.

References:

• keypad issue - Microsoft Q&A