ORA-00259: log string of open instance string (thread string) is the current log- cannot archive

ORA-00259: log string of open instance string (thread string) is the current log- cannot archive
Cause: An attempt was made to archive the current log of an open thread. This is  not allowed
because the redo log file may still be in use for the generation of redo  entries.
Action: Force a log switch in the instance where the thread is open. If no instances  are open, open the database so that instance recovery can recover the thread.