Homegroup issues with Vaio Laptop

I have 4 dell pcs and a Vaio Laptop all running Win7 Pro. I have set up a homegroup on all pcs which works as it says on the tin when the laptop is connected to the LAN network via a docking station. So this tells me I have set everything up correctly.

The problem comes when the laptop is disconnected from the LAN. Now the Vaio is not accessible from the homegroup. I can see the user under homegroup, but if i go to any folder I get nothing. Clicking on properties says " properties for this item are not available".

I have checked that "File sharing for MS networks" is checked on in the wireless adapter. Since it works on the LAN I'm not sure what else to check. Any ideas gratefully recieved as very frustrated the new "killer" home networking solution form MS doesn't just work!

Mike

Found my own solution. Laptop was running Kapersky IS 2010 and needed to go to:

settings->System security->Firewall (settings)-> Networks tab

Set every network conenction to Trusted and now works fine. Guess it trusted the LAN conenction automatically but not the wireless connection.