What happens when a subpoena cannot be served?

When a subpoena cannot be served, the issuing party may seek alternative methods to ensure it is delivered, such as using a process server, certified mail, or obtaining a court order for service by publication. If service remains unsuccessful, the party may file a motion with the court to address the issue or request an extension. Failure to serve a subpoena can delay legal proceedings and may lead to the court dismissing the case or excluding key evidence if proper procedure isn't followed.