Okta AD agent error "The client and server cannot communicate, because they do not possess a common algorithm"

The AD Agent does not connect after startup

If the AD Agent does not connect after startup and the agent logs contain an exception:

The client and server cannot communicate, because they do not possess a common algorithm

Make sure that TLS 1.2 is enabled on your OS. For Windows 2008 R2 TLS 1.2 is disabled by default and needs to be enabled through the registry. Ensure the following regkeys are set correctly:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server] "Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server] "DisabledByDefault"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client] "Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client] "DisabledByDefault"=dword:00000000