Windows Server 2008 R2 come with IIS 7.5, latest supported TLS version is 1.1. Recently Google Chrome starting showing sites using TLS 1.0 and 1.1 as insecure.
To fix this, create a file tls12-enable.reg with following content
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client] "DisabledByDefault"=dword:00000000 "Enabled"=dword:00000001 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server] "DisabledByDefault"=dword:00000000 "Enabled"=dword:00000001
Now run a command promt (cmd.exe) as Administrator. Go to the folder where tls12-enable.reg is saved, run
reg import tls12-enable.reg
Now reboot your server. Once server is back online, check if server is supporting TLS 1.2 using
https://www.ssllabs.com/ssltest/analyze.html
If TLS 1.2 is showing as enbaled, we can disable all older insecure protocols, for this, create a file disable.reg with following content
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Client] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Server] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Client] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Client] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Server] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server] "DisabledByDefault"=dword:00000001 "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 128/128] "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 40/128] "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 56/128] "Enabled"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\KeyExchangeAlgorithms\Diffie-Hellman] "ServerMinKeyBitLength"=dword:00000800
Start a command promt as user Administrator, navigate to folder where disable.reg is saved, run command
reg import disable.reg
Reboot server. once server is back online, you will have all disabled protocols disabled. ssllabs will show Score A.