This article describes how to edit the registry to change the default maximum transmission unit (MTU) size settings for Point-to-Point Protocol (PPP) connections or for virtual private network (VPN) connections. Original KB number: 826159 Summary Windows Server 2003, Windows 2000, and Windows XP use a fixed MTU size of 1500 bytes for all PPP connections and use a fixed MTU size of 1400 bytes for