[Davve]

Har trådlöst internet hemma och 2 bärbara uppkopplade. Min fungerar utmärkt men tjejen har nåt skumt problem som jag aldrig tidigare sett.

Hon kommer åt vissa sidor när hon surfar, men andra visas inte. Vad kan det bero på? Stora sidor som aftonbalet, google osv visas inte, sidan kan inte visas står det bara

Vad kan man göra?

Hon har XP installerat och surfar med IE 6.0

Det skummaste är att vissa sajter funkar men inte andra

[WebboT]

Hittade detta vid en snabb googling:

You've got a packet-size (MTU) problem. When connected via the router, you're effectively on a small LAN, with the router acting as a server for the Internet.

Maximum packet size on a LAN is 1500 bytes, so W2K network s/w, the router and the remote webserver should negotiate to ensure that returned packets don't exceed that size. Unfortunately there can be a screw-up when secure protocols are in use - both Hotmail and MS use such protocols. You'd have problems with eBay as well - I did.

What is happening is that an extra "header" has to be added to the incoming packet for the NAT router to "post" it to the correct destination on the internal network. If the website erroneously returns a 1500-byte packet, the router can't send it on to the PC, as with the NAT header added it would be bigger than the network limit. That this is happening is confirmed by the fact that a straight dialup link works fine.

The solution is to reduce the MTU for the PC-Router interface. It can be done manually by editing the registry, but it can be quite difficult identifying the entries for the interface in question. I suggest you get hold of a free "tweaking" utility like TCP Optimizer to reduce the MTU. A reboot will be needed for the change to take effect.
The utility has a "Largest MTU" test tab - play with this accessing your problem sites, and it'll show you what the setting should be - it was 1486 for me.

I recommend you don't set the "TCP Receive Window" to the ridiculously large figure suggested by the utility. It's just not necessary - I have 8Mbit broadband, and 65535 gives me maximum d/l rate (over 800K/sec.)

[Davve]

Kan tilläga att när jag installerade om hennes dator för någon vecka sedan så funkade allt utm'rkt efter det. Detta har börjat strula nyligen för någon dag sedan, hon säger att hon inte har ändrat några inställningar vilket gör det hela ännu mer konstigt. Hur kan det bli så utan att man ändrar nåt?

[Davve]

Det är nåt fel på IE, löste sig med nyinstalation