Microsoft SQL Server database ranks third in the relational database, second only to Oracle and MySQL database. when using it, it is inevitable to encounter various problems and warnnings. You may be dba or a developer, I hope this content can help you solve SQL Server error number 18491.

Error number: 18491

Severity level: 16

Event logged: SQL Server could not start because of an invalid serial number. The serial number information retrieved at startup appears invalid. To proceed, reinstall SQL Server.