Home Network Problem

[stumpy6]

Hello all.
I have a slight problem in which im pulling my hair out (and i ain't got much to start with).
My problem is this.
I have connected to my home network 1 PC and 2 netbooks. (1 of which is mine and 1 is my daughters). Up till about a week ago the home network was working ok. Now i cant see my daughters netbook from my pc. I can from my netbook, my daughter can see my pc. She can also see my netbook.
Ive ran the trouble shooter and also started a new home network but still the same outcome she can see me but i can see her.
Both Netbooks are using Windows 7 Home Basic. My PC is running Windows 7 Ultimate X64
Im using Norton Internet Security on both my PC and netbook, She is using AVG internet Security (came with the netbook)
Both Netbooks are Samsung (Mine NC10 hers NC130). My PC is a self build.
Any ideas on what i can do next to get my PC to see her Netbook as we need it as i pass work etc to her when she uses my PC.
Thanks

 

[KIA]

I'd ditch/disable the shoddy internet security packages on both machines.

See if you can ping each other and attempt to browse to the computer using \\computer_name

 

[stumpy6]

Thanks but how will that make a difference.
When i use my netbook i can see hers. As i have said i can see my netbook but not my daughters from my desktop.

 

[KIA]

The security software may be acting as a firewall and blocking traffic. Please carry out the tests and let me know how you get on.

I don't know if you're actively paying for the security software. I would recommend Windows Firewall, Security Essentials and OpenDNS. All free.