[Resolu] Connexion HTTP possible pendant - 10 minutes bloque pour ne jamais revenir

Un problème peut banal pour moi.
Je démarre le PC sous XP home, je peux naviguer avec Firefox et lire mes mails tout de suite.
Au bout de 10 minutes environ, toutes opérations vers le net sont interdites à l’exception notables des pings.

ping www.free.fr et ping www.google.fr fontionne très bien.

J’ai soupsonné Norton Internet Security et je l’ai désintallé car en déactivant le firewall comme d’habitude ça ne revenait pas.
Depuis un portable sous XP pro, j’accède à internet et je n’ai aucun soucis donc le réseau est ok, le routeur est ok et la freebox aussi.

J’ai installé avast sur le pc à problème après avoir désinstaller NIS et celà semblait fonctionner. Un reboot plus tard et rebelote, au bout de 10 minutes, firefox devient gris et thundedird ne trouve plus ses serveurs POP, RSS et IMAP.

Seul le ping fonctionne mais tous les autres non:

  • nslookup
  • IE, OE
  • firefox, thunderbird et filezilla.

Ce que je ne comprends pas c’est pourquoi au bout de 10 minutes de fonctionnement j’ai un blackout d’internet. :grrr:
Je précise que

  • le firewall SP2 est normallement déactivé selon sa console de gestion.
  • Avast, WindowsDefender et NAV n’ont pas trouvé de virus, trojan ou autres malveillants.
  • je n’ai pas de firewall installé dessus (-> Linksys fait le boulot à partir de maintenant)
  • ai mis les dernières mise à jours windows

Y’a t-il d’autre chose à voir avant d’envisager une réinstalle de Windows?

Tente un antivirus en ligne (secuser.com par exemple).

Quand tu ping, ça retourne la bonne IP ? Parce que tu disais nslookup ne marchait pas.

Pour les pings, ils sont confirmés par le second PC.
Je fais le nslookup sur le pc portable et je fais le ping sur le pc donc les navigateurs sont bloqués.

Plus j’essaye, plus je me dis que le firewall se met en route ou qu’un truc fait office de firewall sur le PC. Pour essayer, j’ai ajouté une redirection sur mon routeur Linksys pour les 1024 premier ports.

Résultat:
[color=#3333FF]0
<nil>
Closed Your computer has responded that this port exists but is currently closed to connections.

21
FTP
Closed Your computer has responded that this port exists but is currently closed to connections.

22
SSH
Closed Your computer has responded that this port exists but is currently closed to connections.

23
Telnet
Closed Your computer has responded that this port exists but is currently closed to connections.

25
SMTP
Closed Your computer has responded that this port exists but is currently closed to connections.

79
Finger
Closed Your computer has responded that this port exists but is currently closed to connections.

80
HTTP
Closed Your computer has responded that this port exists but is currently closed to connections.

110
POP3
Closed Your computer has responded that this port exists but is currently closed to connections.

113
IDENT
Closed Your computer has responded that this port exists but is currently closed to connections.

119
NNTP
Closed Your computer has responded that this port exists but is currently closed to connections.

135
RPC
OPEN! (Remote Procedure Call) This impossible-to-close port appears in most Windows systems. Since many insecure Microsoft services use this port, it should never be left "open" to the outside world. This port has been exploited to send "Messenger Spam" pop-ups to Microsoft windows users. Since it is impossible to close, you will need a personal firewall or NAT router to block it from external access. Do it soon!

139
Net
BIOS
OPEN! As you probably know by now, the NetBIOS File Sharing port is one of the largest security holes for networked Windows machines. The payoff to Malicious hackers from finding open Windows shares is so big that many scanners have been written just to find open ports like this one. Closing this port is not difficult and it should be a priority for you!

143
IMAP
Closed Your computer has responded that this port exists but is currently closed to connections.

389
LDAP
Closed Your computer has responded that this port exists but is currently closed to connections.

443
HTTPS
Closed Your computer has responded that this port exists but is currently closed to connections.

445
MSFT
DS
OPEN! This impossible-to-close port first appeared on Windows 2000 and was carried over to Windows XP. Since several insecure Microsoft services use this port, it should never be left “open” to the outside world. Since it is impossible to close you’ll need a personal firewall or residential NAT router to block this port from external access. Do it soon!

1002
ms-ils
Closed Your computer has responded that this port exists but is currently closed to connections.

1024
DCOM
Closed Your computer has responded that this port exists but is currently closed to connections.

1025
Host
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

1026
Host
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

1027
Host
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

1028
Host
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

1029
Host
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

1030
Host
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

1720
H.323
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

5000
UPnP
Stealth There is NO EVIDENCE WHATSOEVER that a port (or even any computer) exists at this IP address!

[/color]

Il n’y a pas de firewall pour bloquer le traffic entrant à priori d’après ce que je remarque. Mais, je ne peux pas sortir :frowning:

J’ai désintallé les dernières mises à jours de Microsoft et celà semble revenir à la normal.

30 minutes et toujours pas de blocage.