SSL port specified is not allowed

The only reference I could find is this:

1535 ? Message: 12204 SSL Port Specified Is Not Allowed.
The Web Proxy service makes HTTPS requests on port 443.
A connection request that specifies a different port will generate the subject message.You can add additional ports using Regedt32, but allowing these through your Proxy Server may introduce a security risk.

To add additional ports, navigate to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W3Proxy\Parameters

Double click the SSLPortListMembers value name, a type REG_MULTI_SZ, that defaults to:

443
443
563
563

Add the additional ports, in duplicate, to the end of the list. For example, to add port 444:

443
443
563
563
444
444