I have an HP Envy laptop which notified me that I should update the Radeon driver, which I did. It is now Radeon Software version 19.10.02.13.
However, I have an SD card drive that I assigned letter S. When I re-booted it was re-assigned to Drive D. I tried running Disk Management to assign it back to S. It allows me to do it, but gives a message "The volume in Disk 2 (D) Simple Volume is currently in use. If you continue the new drive letter will be assigned, but you can still use the old drive letter to access the volume until you restart the computer. The old drive letter will not be available for assignment until you restart.". Windows Explorer then shows the drive as S, but when I restart it reverts back to D.
I don't have any other apps running, so I think the only program that is using the drive (and apparently blocking Disk Manager) is Radeon. I have tried closing any apps I don't recognise through Resource Monitor, but whatever I do I can't re-assign the drive.