archive log format error....

Hello All,
I am having an error that I am unable to get around.. It is:
ORA-00249 : Invalid archivelog format specifier '0'

The parameter value for that is the default one which is :
log_archive_format : %ORACLE_SID%%S.%T

Any help will be grately appreciated..

Thanks in advance,
Dee.

What version and OS ? Try following format:

Edit the LOG_ARCHIVE_FORMAT parameter, using %s to include the log sequence number as part of the filename and %t to include the thread number. Use capital letters (%S and %T) to pad the filename to the left with zeros. For example, enter:

LOG_ARCHIVE_FORMAT = arch%t_%s.arc