macbook and pc not communicating on fios network

i have a unibody macbook wirelessly connected to my fios network and have a dell desktop wired to the router, and sometimes when i go to the network tab in finder nothing shows up, and even when i connect to the server manually it doesnt work, and i have both computers on the same workgroup and have all the sharing settings set at low security, but still nothing. sometimes though the desktop shows up in the finder and i can connect fine, and even other times it will only show up after i connect to the server manually. i dont know whether this is the fios networking because it is pretty restirctive cause u cant change ur router and other things like that that comcast can do. my router is a actiontec MI424-WR rev. C

FIOS has nothing to do with it - and the ActionTec router is just like any other router with the exception that it has a network interface module included so you can get your TV guide on screen. You can change the settings in your ActionTec by typing its address in Safari and then enter the setup menu. It's actually a very good configurable router. (check the manual that came with it) The only thing FIOS restricts to some extent are DNS settings but you can work around that too.

Make sure you have the firewalls setup to allow the network to see both machines. It sounds like it works sometimes. Intermittent?

Regards.