Technology Tales

One way to fix slow CyberGhost VPN connections on Windows 10

31st January 2020

Due to a need to access websites with country blocking, I have decided to give CyberGhost a go and it also will come in handy when connecting devices to other Wi-Fi connections. What I have got is the three year subscription package and all went went well on the first day of use. However, things became unusable on the second and a reboot did not sort it.

The problem seemed to affect a phone running Android too and I even got to suspecting my router an broadband provider. Even terminating the subscription came to mind but it did not come to that. Instead, I did a bit more research and tried changing the maximum transition unit (MTU) for the connection to 1300 as suggested in a CyberGhost help article. Using the Control Panel meant that it was resetting to 1500 on my Windows 10 machine so I then turned to a command line based solution.

To do that, I started PowerShell in administrator mode from the context menu produced by right clicking on the Start Menu icon on the taskbar. Then, I entered the following command to see what connections I had and what the MTU settings were:

netsh interface ipv4 show subinterfaces

From looking through the Settings and Control Panel applications, I already had worked out what network interface belonged to the CyberGhost connection. Seeing that the MTU setting was 1500, I then issued a command like the following to change that to 1300.

netsh interface ipv4 set subinterface "<name of ethernet interface>" mtu=1300 store=persistent

Here, <name of ethernet interface> gets replace by the name of your connection and the string is quoted to avoid spaces in the name causing problems with executing the command. Once that second command had been run, the first one was issued again and the output checked to ensure that the MTU setting was as expected.

This was done when the VPN connection was inactive but it may work also with an active connection. After making the change, I again reconnected to the VPN and all has been as expected since then and I found a better connection for my Android phone too.