How to manually disable SSL 2.0 and SSL 3.0 and make sure that the stronger TLS protocols are used


How to manually disable SSL 2.0 and SSL 3.0 and make sure that the stronger TLS protocols are used

This is a valid concern and we do encourage System Administrators to disable SSL v3 on any Windows systems that the Prognosis Web Interface IIS application has been installed on.


I did some checking and the only problems that we are seeing concerning TLS is when a customer downloads the latest Google Chrome or Firefox browser. Doing this will disallow you to view the Prognosis website not because of a support issue using TLS but because these browsers have stopped supporting SSLv3 handshake in their browser.


Please follow the instructions at

to disable SSL v3. This will force all Web Interfaces to use TLS. I have supplied the details below for your convenience.

Manual fix

Run Regedit as Administrator and navigate to:





Right click Protocols and select New > Key option.


Name the new key as SSL 3.0.


Now right click SSL 3.0 and create a new key named Client.


Again, right click SSL 3.0 and create the key Server.


Right click Client and select  New > DWORD (32bit) Value option.


Name the DWORD as DisabledByDefault. Double click the DWORD and type 1 as Value data then click OK to confirm.


The DWORD Value Data set to 1.


Repeat same procedure for Server and assign Enabled as a DWORD name. Leave default Value Data set to 0.


Restart the server to complete the procedure. 


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