ORA-01017: Invalid Username/Password; Logon Denied – Complete Troubleshooting Guide
ORA-01017: Invalid Username/Password; Logon Denied – Complete Troubleshooting Guide Published: April 2026 Last Updated: July 2026 Reading Time: 12–15 Minutes Applies To: Oracle Database 11g, 12c, 18c, 19c, 21c and Oracle Database 23ai The ORA-01017: Invalid Username/Password; Logon Denied error is one of the most frequently encountered Oracle Database authentication errors. It occurs when Oracle cannot authenticate a user during the login process because the supplied credentials or authentication configuration are incorrect. Although the error message appears straightforward, the underlying cause is not always an incorrect password. ORA-01017 can also result from password case sensitivity, expired passwords, locked accounts, authentication protocol mismatches, incorrect service names, or application configuration issues. This guide explains the Oracle authentication process, common causes of ORA-01017, step-by-step troubleshooting techniques, real-world pro...