Solution
If the hosted Abacus server supports TLS 1.0 and TLS 1.1 then these will need disabling for security reasons. Old TLS protocols can be disabled in Windows by updating the Windows registry. Follow these simple instructions in order.
Note: Before making any changes to the registry please ensure a backup is taken beforehand.
Open registry utility
To make your changes, you’ll need to open the registry utility.
Click start, then type run.
In the run box, type regedit, then click OK.
Navigate to this path: Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols
Create key records
The next step is to create your key records.
Right-click Protocols.
Point to New, then click Key.
Rename your key as TLS 1.0.
Create another registry key client under your TLS 1.0 key so it looks like this screenshot.
Right-click on Client.
Point to New, then DWORD (32-bit) Value.
Rename the DWORD (32-bit) Value to Enable.
Create another item, DisabledByDefault, underneath TLS 1.0.
Set the DisabledByDefault hexadecimal value to 1.
Repeat steps four to nine to create Server and corresponding keys.
To disable TLS 1.1 on the Windows server, follow these steps, creating TLS 1.1 and corresponding keys.
To finalise your settings, restart your Windows server.