How to Change MTU Value on Windows

Before you begin, please make sure that:

• You have a working internet connection
• Connected VPN on Windows supported device
• A Premium PureVPN account (if you haven’t bought it yet, click here to buy)

To set the best MTU value and optimize VPN speed, please perform the following steps:

First connect VPN. If you are using PureVPN Client then it will automatically create VPN connection named PureVPN. If you created the connection manually then it will appear in Step 3 and you need to modify the command given in Step 4.

• Open Command Prompt. Make sure that you have Admin privileges.

On Windows XP, Vista and 7, Click on Start button and click on Run, type cmd and click OK.

• On Windows 8, right click at bottom left corner and select Command Prompt (Admin).

• Type the below command and hit enter to check current MTU value.
• Note down the current MTU value in case you want to revert changes.

netsh interface ipv4 show subinterfaces

• Type the command below and hit enter.

ping www.google.com -f -l 1500

If the reply you get is Packet needs to be fragmented but DF set, then you have to try a lower MTU value. Keep decreasing the value by 10, i.e. 1490, 1480, 1470 until you get a successful reply. Start increasing the MTU value with small increments after you get a successful reply. Eventually, you will arrive on a value on which packets will not fragment, add 28 to that value (IP / ICMP headers).For instance, if you got the last successful reply on 1470, then add 28 to it, 1470+28 = 1498.

• This number is your MTU value.

If you are using a LAN connection, then type the following command:

netsh interface ipv4 set subinterface PureVPN mtu=1498 store=persistent

OR

netsh interface ipv4 set subinterface PureVPN mtu=1498 store=persistent

where PureVPN is the VPN Connection name.

Recommended:

If some websites are not loading while connected to VPN then please do the following

netsh interface ipv4 show interfaces

netsh interface ipv4 set subinterface X mtu=1432 store=persistent (where ‘x’ is the ID of the interface)