Sudden and inexplicable "IAStorUI has stopped working" error CLR20r3, or "Intel rst is not running"

This only applies to systems that use Intel Rapid Storage Technology drivers.

The symptoms on this one are any of the following:

• Hot-swap SATA bays and other hot-swap SATA devices not being recognized when plugged in and out
• "Intel rst is not running" when hovering over the Intel Rapid Storage Technology icon in the system tray
• "IAStorUI has stopped working" with error code CLR20r3 when trying to start Intel Rapid Storage Technology

More than likely, your BIOS has somehow gotten the SATA configuration changed from "AHCI mode" to "IDE mode".  Reboot, go into your BIOS, and change it back.


For those wondering just why in hell you would ever change it in the first place, there are reasons.  For example, I back up my system with a BartPE bootable CD-ROM, and my BartPE build doesn't have drivers to support the mainboard operating in AHCI mode. 

This means that to back up, I change to IDE mode, then change it back when I'm done.  Although I guess I forgot to change it back last time.

Why Intel hasn't responded anywhere on this issue is beyond me.  Code CLR20r3 must mean "No AHCI adapter detected" or something equally obvious.  Why can't the program throw a textual error to that effect instead of ingloriously crashing?