Error: The data source is not properly configured for Microsoft 365 authentication

Overview

When trying to sign in to your Business Central Public Cloud data source, you encounter the following message:

The complete text of the error message is:

The data source is not properly configured for Microsoft 365 authentication: AADSTS1002016: You are using TLS version 1.0, 1.1 and/or 3DES cipher which are deprecated to improve the security posture of Azure AD. Your TenantID is: TenantIDPlease refer to https://go.microsoft.com/fwlink/?linkid=2161187 and conduct needed actions to remediate the issue. For further questions, please contact your administrator.

Resolution Process

You need to force .NET to use TLS 1.2 instead of TLS 1.1/1.0 on any machine encountering this error.

To enforce TLS 1.2:

1. Open Windows Powershell as an Administrator.
2. Enter the following commands:

   Set-ItemProperty -Path 'HKLM:\SOFTWARE\Wow6432Node\Microsoft\.NetFramework\v4.0.30319' -Name 'SchUseStrongCrypto' -Value '1' -Type DWord
   					Set-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\.NetFramework\v4.0.30319' -Name 'SchUseStrongCrypto' -Value '1' -Type Dword
   				

3. Restart Excel.
4. Sign into your Business Central Public Cloud data source.

Note: It is recommended to always back up the Windows Registry before making any changes.