MTU (Maximum Transmission Unit)

Symptoms

An incorrect MTU setting on your router can often cause websites to load incorrectly with errors, or not at all. This usually occurs with dynamic or secure web pages. Most pages will load fine, but some financial websites, and web based email (ex: Hotmail, Yahoo, Gmail) won’t load correctly.

Cause

This happens because the website you’re trying to access is sending a packet that is too large for your connection to handle and gets dropped.

Resolution

The correct MTU setting for any device plugged directly into our network is 1480 Bytes. If you’re connected directly without a router the MTU size is normally obtained automatically and is rare that you’ll have to manually set your MTU. Some routers on the other hand have a problem obtaining the MTU size dynamically and it needs to be set manually.

This setting is normally found under the “Setup” page for your router. It’s also found under the Advanced, Firewall, or WAN pages depending on your router’s manufacturer.

If you need step by step instructions on how to change your MTU setting call or email technical support for further assistance and reference this Knowledge Base article.

Related Articles:

http://linksys.custhelp.com/cgi-bin/linksys.cfg/php/enduser/stdadp.php?pfaqid=3982#mtu

http://support.dlink.com/faq/view.asp?prod_id=962&question=MTU+setting