Why can't Windows 7 see my Mac

[nmk.skiier]

Why can't my Windows 7 PC see my MacBook Air? My MacBook Air sees my Window 7 machine, but Windows 7 can't see my MacBook Air. As far as I can tell, I have sharing ON in my MacBook Air. The 2 are in the same workgroup and I have homegroups disabled on my Windows 7 machine. I have been searching all over for the answer. I found a similar problem here, but the solution doesn't apply to me as I have already disabled homegroups on Windows 7...