I have a rather strange issue with my netbook on my local network. When trying to connect to it in any way from a remote system it does not appear to find it. However if I get the netbook to ping the machine trying to connect it mystically appears to work.

Below is the ping test from my main PC to the netbook.

C:\Users\Sam>ping 192.168.8.102

Pinging 192.168.8.102 with 32 bytes of data:
Reply from 192.168.8.100: Destination host unreachable.
Reply from 192.168.8.100: Destination host unreachable.
Reply from 192.168.8.100: Destination host unreachable.
Reply from 192.168.8.100: Destination host unreachable.

Ping statistics for 192.168.8.102:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Now a ping from the netbook to my main PC

sam@malamute ~ $ ping 192.168.8.100
PING 192.168.8.100 (192.168.8.100) 56(84) bytes of data.
64 bytes from 192.168.8.100: icmp_req=1 ttl=128 time=2.46 ms
64 bytes from 192.168.8.100: icmp_req=2 ttl=128 time=0.835 ms
64 bytes from 192.168.8.100: icmp_req=3 ttl=128 time=1.60 ms
64 bytes from 192.168.8.100: icmp_req=4 ttl=128 time=1.32 ms
64 bytes from 192.168.8.100: icmp_req=5 ttl=128 time=1.34 ms
^C
--- 192.168.8.100 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4004ms
rtt min/avg/max/mdev = 0.835/1.514/2.460/0.536 ms

And the same ping again from the main PC after the netbook has made a connection to it

C:\Users\Sam>ping 192.168.8.102

Pinging 192.168.8.102 with 32 bytes of data:
Reply from 192.168.8.102: bytes=32 time=1ms TTL=64
Reply from 192.168.8.102: bytes=32 time=1ms TTL=64
Reply from 192.168.8.102: bytes=32 time=1ms TTL=64
Reply from 192.168.8.102: bytes=32 time=1ms TTL=64

Ping statistics for 192.168.8.102:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 1ms, Maximum = 1ms, Average = 1ms

The netbook is running Gentoo and is currently connected via wireless.

My main PC is running Windows 7 however I get the same result no matter what PC I use on this network. Please see this example from a CentOS machine on the same network

[root@tiger ~]# ping 192.168.8.102
PING 192.168.8.102 (192.168.8.102) 56(84) bytes of data.
From 192.168.8.200 icmp_seq=2 Destination Host Unreachable
From 192.168.8.200 icmp_seq=3 Destination Host Unreachable
From 192.168.8.200 icmp_seq=4 Destination Host Unreachable

--- 192.168.8.102 ping statistics ---
6 packets transmitted, 0 received, +3 errors, 100% packet loss, time 5000ms
, pipe 3

If you need any more information or require logs or config files please let me know and any assistance is greatly appreciated.

Additional info:

No responses on TCP dump from the netbook.

Same result when booting into Ubuntu from a USB key.

No issue when using a wired Ethernet connection.