Second Hard drive not show up in Finder

Further to my question. I did a Spotlight search for a file that may be on the drive and found it clicked it and Finder opened up with the File, scroll back to see where the file was on and it shows up as the "lost" file, but it appears "dimmer' than all the other drive Icons, I can view other files, folders in that drive, it's only when I try the back button or select something else that the drive dissapears again.

Oh, and I guess the "hidden" drive is the original Apple drive that came with the system, a Hitachi 500Gb drive, as I relaced it with a SSD. And I don't see it on the desktop even though in preferences I have selected to see the drives there, of which I see my SSD OS drive. Thanks.

Yes, an external USB drive mounts perfectly, thanks.

So, have been onto Apple Support after finding Apple Chat a little dissapointing. It turns out, maybe, that when Mavericks was installed, the new OS saw 2 hard drives, the SSD drive and the spinning disk hard drive and assumed that it was a Fusion drive and hence that is the situation now although I imagine the directories are all screwed up. I can do a search for files and folders that are on my 2nd HDD but can't see them naturally in Finder. This has now been ecscallated to Apple Engineering so may hear back in hopefully 4 days time!?

My advice if you have a Mac Mini with two drives like mine with an SSD as OS drive, is to put off upgrading to Mavericks, unless you want a "Fusion" drive, but back your DATA up first, and that includes the data on the 2nd drive!!!

Ho hum!!!

So, just an update. I have another Mac Mini, of which has similiar setup, although I think both internal drives are SSD, so this may have been the difference. Or it was a fluke that Mavericks installed on the other Mac Mini and assuming that the drives should be Fusion.

I since have tried reformatting the OS SSD drive and Cloned a fresh instal of ML onto it (for some reason a Lion or Mountain Lion USB installer disk wasn't working, maybe because it was still in (Fusion mode"). Even in Mountain Lion though, it was still behaving like a Fusion drive machine. So with the following advice http://www.macworld.com/article/2015664/how-to-split-up-a-fusion-drive.html I split the drives using Terminal having backed up the drives first! And then was able to instal from a USB stick ML again, and it is all good now!!

So I'll wait until the New Year before I update this machine to Mavericks, when I have some time!!

An odd one!!

I've ticked and un ticked and re ticked the options to show drives. Hence why only the OS drive shows up on desktop but not 2nd drive!?

Good call, unfortuantely, this did not help. Tried trashing a few times, restarting and still no drive.