Originally posted by: Pro Pete
Make sure the backup of the TLOG does not include the NO_TRUNCATE option as that would leave all the backed up log entries still sitting in the Log file and not marked for re-use.
Also check how much of the Log file is actually being used, because truncation of the Log does not release space to the OS, only allows it to be re-used by SQL. You may find that it has grown that big gecause it was used at some poiint and has never been shrunk back.
In the Database Maintenance Plan, under the Transaction Log Backup tab, I do not see an option for NO_TRUNCTATE. Is there another location that can be verified that it is not set?