Enabling TLS 1.2 IN server

Steps to enable the TLS 1.2 in server:

  1. Start Registry Editor. To do this, right-click Start, type regedit in the Run box, and then click OK.
  2. Locate the following registry subkey:HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols
  3. Right-click the Protocol key, point to New, and then click Key.

    Registry
  4. Type TLS 1.2, and then press Enter.
  5. Repeat steps 3 and 4 to create keys for TLS 1.1, & TLS 1.3. These keys resemble directories.
  6. Create a Client key and a Server key under each of the TLS 1.0, TLS 1.1, and TLS 1.2 keys.
  7. To enable a protocol, create the DWORD value under each Client and Server key as follows:
    1. DisabledByDefault [Value = 0]
      Enabled [Value = 1]
  8. To disable a protocol, change the DWORD value under each Client and Server key as follows:
    1. DisabledByDefault [Value = 1]
      Enabled [Value = 0]
  9. On the File menu, click Exit.

https://support.microsoft.com/en-us/topic/tls-1-2-protocol-support-deployment-guide-for-system-center-2016-58f3daa8-655e-e9e7-dafe-cbbd28203118

To check if TLS 1.2 is enabled:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client\DisabledByDefault is present, the value should be 0.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client\Enabled is present, value should be 1.

Other issue:

http://forums.iis.net/t/1205752.aspx?IIS+7+5+FTP+over+SSL+error+with+TLS+1+2+