The default Windows built in L2TP client uses 3DES, and for VPN connection I need to use AES to AES256, so I found command to use Powershell to edit a connection:

Set-VpnConnectionIPsecConfiguration -ConnectionName L2TP -AuthenticationTransformConstants SHA196 -CipherTransformConstants AES128 -DHGroup Group14 -EncryptionMethod AES128 -IntegrityCheckMethod SHA1 -PfsGroup PFS2048 -Force

This does work on a test machine, I was able to connect to a Cisco ASA. My problem is on the PC that needs VPN connections I get this error:

Set-VpnConnectionIPsecConfiguration : Invalid namespace
At line:1 char:1
+ Set-VpnConnectionIPsecConfiguration -ConnectionName L2TP -Authenticat …
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : MetadataError: (PS_VpnConnectionIPsecConfiguration:root/Microsoft/…ecConfiguration) [Set-VpnConnectionIPsecConfiguration], CimException
+ FullyQualifiedErrorId : HRESULT 0x8004100e,Set-VpnConnectionIPsecConfiguration

Not much of a Windows user, even less so with Powershell. Googling ‘Invalid namespace’ to ‘CIMexception’ has not gotten me anywhere, and I have yet to find anything specific to someone else encountering this error when modifying VPN connection. I also get this Invalid namespace when trying to add a new connection via Powershell as well.

​The default Windows built in L2TP client uses 3DES, and for VPN connection I need to use AES to AES256, so I found command to use Powershell to edit a connection:Set-VpnConnectionIPsecConfiguration -ConnectionName L2TP -AuthenticationTransformConstants SHA196 -CipherTransformConstants AES128 -DHGroup Group14 -EncryptionMethod AES128 -IntegrityCheckMethod SHA1 -PfsGroup PFS2048 -ForceThis does work on a test machine, I was able to connect to a Cisco ASA. My problem is on the PC that needs VPN connections I get this error:Set-VpnConnectionIPsecConfiguration : Invalid namespace
At line:1 char:1
+ Set-VpnConnectionIPsecConfiguration -ConnectionName L2TP -Authenticat …
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : MetadataError: (PS_VpnConnectionIPsecConfiguration:root/Microsoft/…ecConfiguration) [Set-VpnConnectionIPsecConfiguration], CimException
+ FullyQualifiedErrorId : HRESULT 0x8004100e,Set-VpnConnectionIPsecConfigurationNot much of a Windows user, even less so with Powershell. Googling ‘Invalid namespace’ to ‘CIMexception’ has not gotten me anywhere, and I have yet to find anything specific to someone else encountering this error when modifying VPN connection. I also get this Invalid namespace when trying to add a new connection via Powershell as well.  Read More

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