TCP não funciona sem fio, mas IP e UDP fazem

Eu tenho um netbook Acer Aspire One (722-0828), rodando o Windows 7 Home Premium de 64 bits.

Quando conectado via cabo ethernet, a rede funciona normalmente.

Quando conectado via wifi, o IP funciona, o ICMP funciona, o DNS funciona:

C:\Users\Tony>ping google.com

Pinging google.com [74.125.225.196] with 32 bytes of data:
Reply from 74.125.225.196: bytes=32 time=27ms TTL=54
Reply from 74.125.225.196: bytes=32 time=24ms TTL=54
Reply from 74.125.225.196: bytes=32 time=36ms TTL=54
Reply from 74.125.225.196: bytes=32 time=28ms TTL=54

Ping statistics for 74.125.225.196:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 24ms, Maximum = 36ms, Average = 28ms

Mas não consigo iniciar conexões TCP da máquina com Windows para nenhum outro lugar. HTTP falha (tentou IE, FF, Opera e Chrome); PuTTY falha (telnet e ssh); o ftp falha, o DNS-sobre-TCP (nslookup com "set vc") falha.

Aqui, eu posso ver que o DNS-over-UDP está funcionando, mesmo para servidores remotos; que me diz que o IP e o UDP estão funcionando. Mas assim que eu faço set vc, a próxima pesquisa trava:

C:\Users\Tony>nslookup
Default Server:  UnKnown
Address:  192.168.1.1

> acer.com
Server:  UnKnown
Address:  192.168.1.1

Non-authoritative answer:
Name:    acer.com
Address:  193.0.238.166

> acer.com 8.8.8.8
Server:  [8.8.8.8]
Address:  8.8.8.8

Non-authoritative answer:
Name:    acer.com
Address:  193.0.238.166

> set vc
> acer.com
Server:  UnKnown
Address:  192.168.1.1

^C
C:\Users\Tony>nslookup
Default Server:  UnKnown
Address:  192.168.1.1

> set vc
> acer.com 8.8.8.8
Server:  [8.8.8.8]
Address:  8.8.8.8

^C
C:\Users\Tony>

Outros dispositivos (laptops OSX, dispositivos iOS, dispositivos Android, outros laptops Windows) funcionam bem na mesma rede Wi-Fi.

Usando um sniffer de pacotes, vejo que a máquina windows envia o pacote SYN inicial, e meu servidor responde com SYN + ACK ... mas a pilha TCP do windows nunca parece vê-la, já que não há resposta, e a máquina windows eventualmente tenta novamente a conexão com outro pacote SYN.

Tentativas de solução de problemas, nenhuma das quais resolveu a situação:

1. Excluído / recriado ambas as interfaces.

2. Redefinir a pilha de ip no Windows.

3. Desabilitou o Firewall do Windows.

4. IPv6 desativado na interface wifi.

5. Confirmou que a rede Wi-Fi é identificada como "Rede doméstica".

Qualquer sugestão seria muito bem vinda.

Aqui está a saída de "ipconfig / all":

C:\Users\Tony>ipconfig /all

Windows IP Configuration

   Host Name . . . . . . . . . . . . : Tony-Netbook
   Primary Dns Suffix  . . . . . . . :
   Node Type . . . . . . . . . . . . : Hybrid
   IP Routing Enabled. . . . . . . . : No
   WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : Atheros AR8152/8158 PCI-E Fast Ethernet C
ontroller (NDIS 6.20)
   Physical Address. . . . . . . . . : DC-0E-A1-51-1C-1D
   DHCP Enabled. . . . . . . . . . . : Yes
   Autoconfiguration Enabled . . . . : Yes

Wireless LAN adapter Wireless Network Connection:

   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : Atheros AR5B125 Wireless Network Adapter
   Physical Address. . . . . . . . . : 60-D8-19-62-F4-0B
   DHCP Enabled. . . . . . . . . . . : Yes
   Autoconfiguration Enabled . . . . : Yes
   IPv4 Address. . . . . . . . . . . : 192.168.1.170(Preferred)
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Lease Obtained. . . . . . . . . . : Wednesday, January 23, 2013 12:38:54 PM
   Lease Expires . . . . . . . . . . : Thursday, January 24, 2013 12:38:54 PM
   Default Gateway . . . . . . . . . : 192.168.1.1
   DHCP Server . . . . . . . . . . . : 192.168.1.1
   DNS Servers . . . . . . . . . . . : 192.168.1.1
   NetBIOS over Tcpip. . . . . . . . : Enabled

Tunnel adapter isatap.{993CDEB4-B0C8-41FD-A3F1-DE951DB1FF9F}:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2
   Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
   DHCP Enabled. . . . . . . . . . . : No
   Autoconfiguration Enabled . . . . : Yes

Tunnel adapter Local Area Connection* 9:

   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
   Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
   DHCP Enabled. . . . . . . . . . . : No
   Autoconfiguration Enabled . . . . : Yes
   IPv6 Address. . . . . . . . . . . : 2001:0:9d38:6ab8:105c:25e6:3f57:fe55(Pref
erred)
   Link-local IPv6 Address . . . . . : fe80::105c:25e6:3f57:fe55%11(Preferred)
   Default Gateway . . . . . . . . . : ::
   NetBIOS over Tcpip. . . . . . . . : Disabled

Tunnel adapter isatap.{88C7FD80-32F0-4C45-9D1A-06EB7A869BB9}:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : Microsoft ISATAP Adapter #3
   Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
   DHCP Enabled. . . . . . . . . . . : No
   Autoconfiguration Enabled . . . . : Yes