How to fix the Oracle error ORA-12528: TNS:listener: all appropriate instances are blocking new connections?

In this post, you’ll learn more about the Oracle ErrorORA-12528: TNS:listener: all appropriate instances are blocking new connections with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-12528: TNS:listener: all appropriate instances are blocking new connections

Reason for the Error ORA-12528: TNS:listener: all appropriate instances are blocking new connections

All instances supporting the service requested by the client reported that they were blocking the new connections. This condition may be temporary, such as at instance startup.

How to fix the Error ORA-12528: TNS:listener: all appropriate instances are blocking new connections ?

You can fix this error in Oracle by following the below steps

Attempt the connection again. If error persists, then contact the administrator to check the status of the instances.