# Reject All Invalid Documents

The `BadFilesFilter` task rejects all documents that are considered to be invalid:

- Documents that have binary content.
- Documents for which import errors have occurred.
- Documents that have too high a proportion of symbolic content.
- Documents where the average word length is too long or too short.

`BadFilesFilter` must be configured as a Post task.

`BadFilesFilter` reads configuration parameters from the section of the configuration file that you specify in the `Post` parameter. In this section you can set parameters for each filter. In the example below, two parameters have been set to configure the word length filter:

    [ImportTasks]
    Post0=BadFilesFilter:BadFilesFilterSettings

    [BadFilesFilterSettings]
    MinimumAverage=3.0
    MaximumAverage=10.0
    OnErrorIndexerSections=IdolErrorServer
    IndexDatabase=IdolErrorReview

For information about the parameters that you can use to configure this task, refer to the Connector Framework Server Reference.

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