Step 1: Locate intermediate certificate file
Locate the intermediate certificate file on your server and right-click it. Click Install Certificate to open the Certificate Import Wizard. The Certificate Import Wizard control panel will open in the center window.
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Step 2: Certificate Import Wizard
Choose Local Machine and click the Next button.
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On the Certificate Store window, click the Next button to proceed.
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On the Completing the Certificate Import Wizard window, confirm the details of the import settings and click the Finish button.
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You should receive a The import was successful message.
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Step 3: Test chain of trust
You can use the SSL Checker online tool to check your server's chain of trust more thoroughly.
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