The problem is, I can't resize it bigger because when I create a new chunk of unallocated disk space, it's not adjacent to that partition. I *think* it's based on the fact my reserved partition isn't large enough. I've also tried disabling all Anti-Virus etc to no avail. I get errors saying something like 'couldn't write to reserved partition' (or something about the reserved partition), and an error code which I forgot but the new error code is: 0xc1900200 I'm not trying to upgrade from Win7/8 to 10 but from Win 10 (Version 1551 (OS Build 10586.1176)) to Windows 10 Fall Creators update. So I'm pretty much out of options after Googling and trying over & over again for a week so I'm hoping someone might have advice: