Need help seeing Readyshare from Vista Laptop please

I have an XP Dell GX270 (wired), Vista Gateway laptop (wireless) and an Win7 Acer laptop (wireless). I have a WNDR3400 w/ the USB port. I have hooked up to it a 1.5TB Sata drive. I can see the drive fine on the XP and Win7, but not on the Vista. I didn't have to change any settings on the other computers and since I set it up months ago, I think I remember "allowing" the readyshare in the router itself (and I currently can't remember the darn router password). I don't know what to change on the Vista. I'm not too good w/ this type of networking (if you want to call it that) so any help would be appreciated.

Thanks. :)