Intel Rapid Storage Technology (Intel RST): The inbox storage driver iastora.sys doesn’t work on these systems and causes stability problems on Windows. Check with your software/driver provider for an updated version that runs on this version of Windows

If you get this error message while trying to upgrade to Windows 10 1903, and you update your storage driver, but this message is still appearing, you have to go into C:\Windows\system32\drivers (WARNING, WHAT I AM ABOUT TO TELL YOU CAN HOSE AND DAMAGE YOUR SYSTEM. PLEASE MAKE SURE YOU HAVE A GOOD BACKUP THAT YOU’VE TESTED. I WOULD CREATE A RESTORE POINT JUST IN CASE YOU GET STUCK, I AM NOT RESPONSIBLE FOR ANY DAMAGES THAT MAY OCCUR TO YOUR COMPUTER BASED UPON THIS INFORMATION) and look for the iaStorA.sys file and rename it to iaStorA.sys_old. However, make sure you are seeing the updated Intel storage driver within Device Manager first.

Once you rename the file, you can go back out and re-run the update. This should get you past this error message.