dsperber said:
No... the partition has NO FILE SYSTEM on it yet. So it must first be formatted with NTFS, before assigning a drive letter to it.

While in Diskmgmt, just select that space (like you show in your screenshot) so that it get cross-hatched (just like it is in the screenshot). Then right-click on it, and select FORMAT from the popup menu and follow the wizard, to format it as NTFS.

Then it will either automatically be given a drive letter by Windows, or you can assign a drive letter manually.
Thats exactly what i did