The SDK Installer is compatible with:

Sage CRM 2021 R1

Sage CRM 2020 R1
Sage CRM 2020 R2

To install the Sage CRM .NET SDK:

Download the Sage CRM .NET SDK installation package for your version of Sage CRM.
Extract the contents of the downloaded .zip file to a temporary folder on your local disk drive.
Run the Sage CRM SDK 2021 v1.0.exe file and complete the wizard that starts.