Note: If you see a yellow exclamation mark (!) next to a device, that is the problematic driver.
This happens when you try to install an ancient SMS software (e.g., from Windows 7 or 8). Windows 11 has strict driver signature enforcement.
Key Takeaway: If you are trying to text from your PC using your phone number, you do not need a driver download; you need the correct software configuration.
MMS (Multimedia Messaging Service) often fails on Windows 11 due to APN (Access Point Name) settings. If SMS works but MMS (pictures/videos) does not:
SMS/MMS Driver on Windows 11: What It Is & How to Fix Missing or Not Working Issues