PPTP or L2TP with Windows Vista / Windows 7 doesn´t work

 

This solution replies to:
- NG Firewall firmware versions 4.2.x, 5.0.x, 5.2.x
- netfence firmware versions 4.2.x

 

No PPTP / L2TP connection to a Barracuda NG Firewall possible with Windows Vista / Windows 7.

 

In Windows Vista / Windows 7 there where a few changes concerning the remote access from security perpective. 40/56 bit RC4 encryption is removed by default from Vista / 7 as well as LHS server. This means PPTP/L2TP now only supports 128 bit RC4 encryption by default. So if you VPN server or VPN client doesn?t support 128 bit encryption, you can still get 40/56 bit RC4 back.

If you still want to do get 40/56 bit RC4 crypto back, use the following registry key:

For PPTP:
HKLM\System\CurrentControlSet\Services\Rasman\Parameters\AllowPPTPWeakCrypto and change it to "1". 

 

HKLM\System\CurrentControlSet\Services\Rasman\Parameters\AllowL2TPWeakCrypto and change it to "1". 


Please restart your machine after that.