Hi,

by default .NET does not uses TLS Version 1.2. So if you disable all SSL/TLS versions lower then 1.2 .NET application could not establish a secure connection anymore.

To set the default TLS version to 1.2 set the following registry values:

reg add HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v2.0.50727 /v SystemDefaultTlsVersions /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v2.0.50727 /v SchUseStrongCrypto /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319 /v SystemDefaultTlsVersions /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319 /v SchUseStrongCrypto /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v2.0.50727 /v SystemDefaultTlsVersions /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v2.0.50727 /v SchUseStrongCrypto /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v4.0.30319 /v SystemDefaultTlsVersions /d 1 /t REG_DWORD /f
reg add HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v4.0.30319 /v SchUseStrongCrypto /d 1 /t REG_DWORD /f

Michael