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I'm getting this error when trying to connect to the Salesforce sandbox API via a .NET SOAP webservice, when using IIS 10. None of the other similar questions I've found on Salesforce Stack Exchange provide a solution that works for me.
UNSUPPORTED_CLIENT: TLS 1.0 has been disabled in this organization. Please use TLS 1.1 or higher when connecting to Salesforce using https.
I've checked in the Salesforce sandbox under 'critical updates', but there is no update related to TLS 1.1 that I could disable.
I've also tried editing my registry using the following guides (one of these is for IIS 7.5 but I tried it anyway as nothing else is working)
What do I need to do to get this to work? the error states that the problem is with the client, so it must be something I need to change at my service end.