Binary or Null Filter
Note
Indexing Service is no longer supported as of Windows XP and is unavailable for use as of Windows 8. Instead, use Windows Search for client side search and Microsoft Search Server Express for server side search.
When a registered binary file is encountered, the null filter (in Query.dll) is used. The null filter retrieves only the system properties. The contents of a binary file are not filtered. Examples of system properties are FileName, LastWriteTime, FileSize, and Attributes.