Oracle Solution for Error ora-12479

ORA-12479: file label string must equal DBHIGH string

What triggered the Error:

A database file had an OS label that did not match DBHIGH. Either DBHIGH was altered or the OS file was relabeled.

What should we do to fix it:

Relabel the file so that its label matches DBHIGH, or alter DBHIGH so that it matches the label on the file.