If you put it in Windows/system32/spool/drivers/color it should show up in Photoshop, although you need to restart Photoshop if you copied the profile over while Photoshop was running. There may be one additional folder under Common Files/ProgramData, but the ones in the main profiles directory as defined by Windows should definitely show up. One thing that can be a little confusing is that Photoshop displays the profiles based on the name embedded withing the ICC metadata, rather than the filename itself. Depending on the tool used to create the profile, this embedded name could be completely different from the filename.