The following applies to Windows XP Pro, 2000 server, and 2003 server.
To change the MTU setting for PPP connections:
1. Navigate to Start > Run, type:
regedit, find the following key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NdisWan\Parameters
2. Add a "Protocols" subkey, add a "0" (zero) subkey to the Protocols subkey as well.
3. Add the following new DWORD values to the "0" subkey you created:
"ProtocolType=800" (hexadecimal)
"PPPProtocolType=21" (hexadecimal)
"ProtocolMTU=nnn" (decimal, where nnn is the desired
MTU value)
4. Restart your PC.
To change the MTU setting for VPN connections:
1. Navigate to Start > Run, type:
regedit, find the following key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NdisWan\Parameters
2. Add a "Protocols" subkey, add a "0" (zero) subkey to the Protocols subkey as well.
3. Add the following new DWORD values to the "0" subkey you created:
"ProtocolType=800" (hexadecimal)
"PPPProtocolType=21" (hexadecimal)
"TunnelMTU=nnn" (decimal, where nnn is the desired
MTU value)
4. Restart your PC.
References:
MSKB 826159
