AHCI problem after BIOS update (solved)

OptiPlex 7010 and Windows 10 Pro. After BIOS update, I had issues with bluescreen. Switched BIOS to ATA and computer worked great. Switched back to AHCI and the bluescreen "inaccessible boot device came back. Ran regedit to confirm all keys were set for AHCI. Still have the issue. No problems with AHCI with BIOS version A23 but version A25 has been nothing but a pain. Any suggestions?

(SOLVED) After reading everything I could on the internet, making all kinds of BIOS and registry changes and rebooting over a hundred times during an 18 hour span - I finally got AHCI to work! here's what seemed to do the trick: set BIOS through F12 on start to ATA so you can get past bluescreen to Windows. In Windows, run "msconfig" and set boot to "safe mode with minimal". Restart and use F12 to change BIOS to AHCI. Then you should go into safe mode. In safe mode, go to "device manager" and make sure AHCI controller shows up. Go to "msconfig" again and uncheck safe mode" boot and restart to Windows in normal mode. NOTE: for some odd reason, I had to do the procedure 2 times for it to take effect. Good luck!