Missing drive in Windows 8

[nanoflower]

I just did an upgrade from Windows XP to Windows 8 and it seems it won't show me one drive. I have three SATA drives plus a DVD burner. Two of the HDs are showing up (Win8 boot plus data partition, WinXP boot plus data partition) and the DVD burner show up fine. However the third HD which is just a data drive isn't showing up in the list of available drive in Win 8. It shows up in the BIOS during boot, and it shows up if I boot into XP but the HD won't show when I boot in Windows 8.

Any ideas as to why a data drive that works fine (SMART tests pass) won't show in Win8 but will show in WinXP? Any suggestions on how to fix this issue?

[Flying Fox]

Check diskmgmt.msc first to see if it is just not assigned a drive letter.

[nanoflower]

Thanks Flying Fox. The drive was there but for some reason the partition hadn't been assigned a drive letter. Not sure why that would happen. Certainly not the expected behavior.