Resolve the Invalid Key error message in Secure Domain

When a pop-up message "This key is invalid or may require a password" appears while pointing a Secure Domain at NetSuite in Setup > Site Builder >Domains >Secure Domains, the first thing to check is how the Private Key was created for the SSL Certificate.

Ensure that the correct commands are used when creating a Private Key (.key) and generating a Certificate Signing Request (.csr).

Note that the Key Password field (in Setup>Website>Domains>Secure Domains) should be populated with the Pass Phrase that was entered upon creating the Private Key (see the article Create a Private Key for your Certificate).

Refer to the Help Center article Certificate Maintenance for information about the Renewal, Replacement, Upgrade and Revocation of SSL Certificates.