1. Open Group Policy Management Console.
2. Find an existing or create a new GPO to contain the certificate settings. Ensure that the GPO is associated with the domain, site, or organizational unit whose users you want affected by the policy.
3. Right-click the GPO, and then select Edit.

   Group Policy Management Editor opens, and displays the current contents of the policy object.

4. In the navigation pane, open Computer ConfigurationWindows SettingsSecurity SettingsPublic Key PoliciesTrusted Publishers.
5. Click the Action menu, and then click Import.
6. Follow the instructions in the Certificate Import Wizard to find and import the certificate.
7. If the certificate is self-signed, and cannot be traced back to a certificate that is in the Trusted Root Certification Authorities certificate store, then you must also copy the certificate to that store. In the navigation pane, click Trusted Root Certification Authorities, and then repeat steps 5 and 6 to install a copy of the certificate to that store.

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