wiki.mbirth.de/know-how/software/windows/_posts/2009-03-18-microsoft.com-not-working.md

---
created: 2009-03-18 20:05:52 +0100
layout: redirect
layout_old: default
redirect_to: https://blog.mbirth.de/archives/2009/03/18/microsoft.com-not-working.html
tags:
- know-how
- software
- windows
title: microsoft.com not working
toc: false
updated: 2009-03-18 20:05:52 +0100
---

If you have a router and Internet works with any application/site but you can't connect to any `microsoft.com` site
(e.g. *WindowsUpdate*, *Windows Live Messenger* [error code: 81000306], etc.) you might have your MTU set to a too high
value. The default MTU for ethernet devices is **1500** but since the PPPoE header adds 8 Bytes to the packets, they
get fragmented. And the `microsoft.com` servers seem to not accept fragmented packets.

So the solution is to set your MTU to the best value for PPPoE: **1492**. To do this, use a tool like the [TCP Optimizer](http://www.speedguide.net/downloads.php)
to set the MTU for your ethernet device to 1492. After a reboot, all `microsoft.com` pages should work again -
including *Windows Live Messenger*.
Updated layout, added UP! marker. Added various Windows posts. 2015-04-13 23:49:46 +01:00			`---`
			`created: 2009-03-18 20:05:52 +0100`
Add redirect to new site. 2022-01-23 17:14:59 +00:00			`layout: redirect`
			`layout_old: default`
			`redirect_to: https://blog.mbirth.de/archives/2009/03/18/microsoft.com-not-working.html`
Updated layout, added UP! marker. Added various Windows posts. 2015-04-13 23:49:46 +01:00			`tags:`
Add redirect to new site. 2022-01-23 17:14:59 +00:00			`- know-how`
			`- software`
			`- windows`
			`title: microsoft.com not working`
			`toc: false`
			`updated: 2009-03-18 20:05:52 +0100`
Updated layout, added UP! marker. Added various Windows posts. 2015-04-13 23:49:46 +01:00			`---`
Add redirect to new site. 2022-01-23 17:14:59 +00:00
Updated layout, added UP! marker. Added various Windows posts. 2015-04-13 23:49:46 +01:00			If you have a router and Internet works with any application/site but you can't connect to any `microsoft.com` site
			`(e.g. WindowsUpdate, Windows Live Messenger [error code: 81000306], etc.) you might have your MTU set to a too high`
			`value. The default MTU for ethernet devices is 1500 but since the PPPoE header adds 8 Bytes to the packets, they`
			get fragmented. And the `microsoft.com` servers seem to not accept fragmented packets.

			`So the solution is to set your MTU to the best value for PPPoE: 1492. To do this, use a tool like the [TCP Optimizer](http://www.speedguide.net/downloads.php)`
			to set the MTU for your ethernet device to 1492. After a reboot, all `microsoft.com` pages should work again -
Add redirect to new site. 2022-01-23 17:14:59 +00:00			`including Windows Live Messenger.`