Build 14271--A recent problem I've had with this build is that when Secure Boot is enabled it interferes with the Samsung Magician software for my EVO 850 250GB boot drive, so that even though AHCI mode is selected for in the bios and supported through Windows, the Samsung Magician software claims it cannot detect any AHCI in the system or read any SATA device information. This started happening just yesterday. The event log identified the problem as the Samsung drivers in Magician being unsigned and as such Secure Boot will not permit the Magician software (4.9.5--the most recent from Samsung) to run its SATA detection routines--so Magician thinks there is no SATA or AHCI in the system. I restored 14271 from a backup to a freshly formatted c:\ (EVO 850) and found that measure ineffective (IE, proving it wasn't malware or damaged files, etc,.) Only thing that works is disabling secure boot--but since I know what the trouble is and that it is superficial (AHCI & Sata are functioning fine in my system) I'll ignore it until the next build. Seems to be a definite bug, though. Weird, how it only just started happening out of the blue...! I gave 'em Feedback on this... Edit: I am happy to report that build 14276 has resolved this little problem!