Ultimately, you should be able to run chkdsk on a volume, as per the chkdks documentation (instead of a drive letter or mount point, you simply pass it the volume name). However, it's probably easier and more reliable to just assign the partition a drive letter or mount point.
Under Windows, you need to assign a partition a mount-point to use chkdsk on it. You can use the Computer Management snap-in (Start -> Run -> compmgmt.msc) or DISKPART to do this (see below for DISKPART instructions). If you go with the Computer Management method, go to the Disk Management section, where you need to assign the partition either:
- A drive letter (i.e. X:)
- A mount path (i.e. X:/MyDisc/)
After this, you should be able to run chkdsk on the particular mount-point of interest. The easiest and most reliable would probably be to mount it as a drive letter.
Alternatively, you can use DISKPART to assign the partition a letter. Fire up DISKPART, and type LIST DISK to find the disk, followed by SELECT DISK <N> (where <N> is the drive number). Follow the same steps to find the proper partition (i.e. LIST PARTITION followed by SELECT PARTITION <N>), and then simply type ASSIGN to have Windows mount the partition at the next new drive letter.