Recognizing Nas Navi Assigned Drives Letters by Windows 7

[Hiero]

   

Here's my problem. I have a router based home network. I used to run Windows XP on all computers attached to the network.  I lost one computer and replaced it with a machine running Windows 7 Home Premium (which I have now upgraded to Windows 7 Professional).  There are two Buffalo Drives on the Network an LS-C500 L and an older HD-HLAN.  I can access the files. They appear in the "network." However, when I attempt to install a program or try to use the windows photo import function, the drive letters for the two drives do not show up.  Neither of them appear in "Devices and Printers."  After upgrading to Pro I was able to do a backup using Windows 7 to one of the drives.  What I see as the problem is that the drive letters assigned to the Buffalo drives are not showing up in the menu like they do when I am running XP (I only get local devices - like the DVD drive or the C: drive)  Any suggestions would be apprecaited (I did do the change about Lan Management that was recommended elsewhere to allow both 1 and 2)   Thanks.