Menu option: Options > Preferences > File types
dtSearch recognizes most file formats automatically. If you are indexing only files such as word processor documents that dtSearch supports and can automatically recognize, you can disregard this section.
If you are indexing other types of files, dtSearch provides a way to specify how you want dtSearch to process the files. For each filter, you can specify a rule that tells dtSearch how you want the file to be handled. You can also use file type rules to override the default handling of some files. For example, you could make a rule to require *.html to be indexed as text, if you want to be able to search HTML tags.
Before using the file type information, dtSearch will try to detect the format itself. Therefore, no matter what file type specifications you enter, dtSearch will recognize formats such as Microsoft Word that it can detect automatically.
dtSearch checks the filename filters in the order that you created them and uses the first one that matches.
To set up a file type specification
1. Click New... to create a new item, and enter a name to identify it
2. Under File type, select the file format that the rule should select.
3. Under Filename filters, enter filters to identify files with this format.
4. Check the Override all other file type detection methods for these files box if you want dtSearch to always apply the rule, even if a document appears to have a different format.
IFilters
IFilters are components that enable various Microsoft search products, such as Microsoft Index Server, to extract text from documents. For example, when you install Microsoft OneNote, an IFilter is installed to enable searching of *.one files. To tell dtSearch to use installed IFilters to process some of your files, set up a rule in the file type table and under File type, select "IFilter".
For more information on IFilters, see http://www.ifilter.org/ or http://channel9.msdn.com/wiki/default.aspx/Channel9.DesktopSearchIFilters.
IFilter support only works on systems with the Microsoft component query.dll installed. Most Windows computers will have this component. For information on products that include query.dll, see http://support.microsoft.com/dllhelp.
Default character encoding
Plain text files, some older word processsor files, and HTML files written in languages other than English use a character encoding to specify the meaning of characters in the range from 128 to 255. For example, a Russian document might have the CP1251 encoding, which uses these characters for Cyrillic letters. By default, dtSearch will try to automatically detect the encoding of these types of documents based on an analysis of the contents. If you find that the auto-detection is not working for your documents, you can specify the encoding that dtSearch should assume for documents that do not specify one. To do this, select an encoding from the drop-down list under Default character encoding.