Just upgraded my MSI laptop with an AC 7260 adapter. Installed latest drivers. Wifi (using 5G) worked great with good speed for a short while, then disconnected. I could then connect using 2.4G, then it would stop. Looking at connections, there would be none available and Wifi on/off button (in software) would not work. No tools could fix. This happens within a few minutes and then I need to reboot system and start again. This is horrific. I tried uninstalling old and new device (then reinstalled), uninstalling other bluetooth devices and drivers, uninstalling "killer network manager". Each time I am in midst of troubleshooting I lose connection and need to start again. I have SSU file for when it is working and when it is not working. I also note it now calls connection "WIFI2"
PLEASE HELP BEFORE I LOSE MY MIND
You cannot "just upgrade your laptop". You must consult MSI regarding supported adapters for their laptop.