Please help with wireless

[Stelios Koulouris]

Untill yesterday I had at home a wired network consisting of three computers
(Lets name them A, B, C) a network bridge, and a DSL modem.

Yesterday I bought to US Robotics Wirelses PCI Adapters (USR-5416) in order
to connect Computers A and C wireless.

So now we have :

Computer A: IP: 194.168.1.3
Subnet: 255.255.0.0
Gateway: 194.168.1.1
Wireless Network Connection (Enabled Bridged) with Computer C
Local Area Connection (Enabled, Bridged) through a Network bridge with DSL
modem and Computer B

DSL Modem: IP: 194.168.1.1
Subnet: 255.255.0.0
Conected to the Network bridge. The connection to internet is RFC1483
Bridged, PPPoE.

Computer B: IP: 194.168.1.5
Subnet: 255.255.0.0
Gateway: 194.168.1.3
Its a Laptop. Conected to the Network Bridge. Gets Internet access through
Computer A and Internet Connection Sharing.

Computer C: IP: 194.168.1.4
Subnet: 255.255.0.0
Gateway: 194.168.1.3
Connected through the Second Wireless adapter with Computer A.
The Signal strength is "Very good"
In the USR LAN Configuration Utility, in the Configuration Tab we have the
same SSID with Computer A (GR) the same network type (Ad-hoc), the same
chanel (2) the same preamble (Long Preamble), but still computer C can't
connect with any other computer in the network, can't access the internet,
can't even "ping" any other computer.

Please any ideas are more than welcome as I am stuck and can't find any
solution to the problem.
I forgot to mention, No data encryption is enabled.
All other Computers works as expected. Network Name: Mshome with different
computer names for each computer.