3. Click 
in the Edit column for the certificate to update, and then do the following on the Edit Certificate Set dialog box:
in the Edit column for the certificate to update, and then do the following on the Edit Certificate Set dialog box: in the Edit column for the certificate to update, and then do the following on the Edit Certificate Set dialog box: 
To remove a private key, select the Clear Private Key check box.To add a private key, click Browse next to Set Private Key and select the private key file.To add a certificate to the chain, click Add Certificate and browse to the certificate to add.To remove a certificate from the chain, select the check box to the left of the certificate to remove, and then click Delete.