Router firewall blocks file transfer

[hitmann]

I have a Netgear dg834pn wireless router and can't transfer files on MSN Messenger since I installed the router. I am not having problems with my Alcatel speedtouch modem.
Now I'm a real newbie at networking. What do i need to do to be able to transfer files normally again?

Also, since I've installed the router, everytime I visit OCuk forums, it doesn't load properly. It either gives the "Cannot find server", or a partialy loaded layout with white background instead of the blue one, or if the blue theme loads, the icons next to thread titles won't. My connection is running full speed, without anything downloading.

Any tips please?

 

[hitmann]

Ok, hold on guys. What does MTU mean? And where do I get it changed to 1400?
The router has the latest firware version installed V1.03.25
I have NOD32 and McAfee Firewall v4.02 installed.
Other websites finish loading correctly, even other vbulletin forums, but take more time than with my older modem. I also had to use my modem to be able to post this reply as it gives me a "Cannot find server" page with the router. I've also noticed that my homepage (yahoo.com) takes a bit more time to load. With the Alcatel Speedtouch, it loads gradually. With the Netgear router, it's has if it's being hold back for 2 or 3 seconds, leaving a blank page, then the whole page loads at once. Weird.


ping and tracert for overclockers.co.uk and forums.overclockers.co.uk result in 4 lost packets out of 4 sent and "Request Time-out".

Pinging Yahoo.com gives this:
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 380.0/381.2/385.0 ms

For BBC.co.uk:
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 240.0/245.0/250.0 ms

tracert for both give "Request Time-out".

My ISP is Telecom Plus, from Mauritius Telecom, don't know if that'll help.

 

[hitmann]

I've stopped McAfee firewall, but the problem is still the same.

EDIT: some icons don't load on the forum, but now I can post a reply, although it takes 10 times longer than usual.

 

[hitmann]

I still can't figure out what's going wrong.

Is there a port I need to open? Does the router firewall need to be turned off?

Help me please...

 

[hitmann]

Anyone?