Oracle Solution for Error ora-01620

ORA-01620: no public threads are available for mounting

What triggered the Error:

The INIT.ORA parameter "thread" is zero, its default value. There are no threads which have been publicly enabled, and not mounted.

What should we do to fix it:

Shutdown the instance, change the INIT.ORA parameter to a thread which is privately enabled and not mounted. If the database is open in another instance, then a thread may be publicly enabled.