Open the folder to which you downloaded the pem certificate, rename it to user.der, and double-click it:
Figure 5 - Selecting a certificate file
The certificate information will open. Click Install Certificate:
Figure 6 - Installing a certificate
The Certificate Import Wizard will start. To import the certificate, follow all the wizard prompts:
Figure 7 - Certificate Import Wizard
Select the certificate store and click Browse:
Figure 8 - Selecting a store
Select Trusted Root Certification Authorities and click ОК:
Figure 9 - Selecting a store (continued)
Click Finish:
Figure 10 - Finishing the import
When the security warning appears, click Yes:
Figure 11 - Consenting to install a certificate
Figure 12 - Installation complete
The certificate is successfully installed.