> Truncation does not physically reduce the size of the log file.
> For that, run
>
> USE myDatabaseName
> DBCC SHRINKFILE (myDatabaseName_Log)
>
> The log file retains all transactions executed on your database unless you > set options to control that, that's why it may be bigger than the actual
> database.

I did with success the command DBCC SHRINKFILE to reduce my log file many times in the past (every month), and now it is unsuccessful. I do not understand why suddenly it do not works. Someone can explain to me why??