Windows 10: use MMC (Microsoft Management Console) to add a trusted CA

1. Right click on the Windows icon. Select menu Run.

2. Input command: mmc

3. In MMC, click on menu File->Add/Remove Snap-in...

4. Select Certificates in the snap-ins list; Click on the Add button. "Certificates - Current User" will be added in the "Selected snap-ins" list. Click on the OK button.

5. In the left panel, expand "Certificates - Current User"; Right click on "Trusted Root Certification Authorities"; Select "All Tasks->Import...".

6. Use the Import Wizard to browse and select the certificate to import.

Note: Only add the CA if you absolutely trust it.