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Indexing scopes (also called crawl scopes and start addresses) are URLs that point to the starting locations for indexed content . When indexing is performed, each configured start address is enumerated by the appropriate protocol handler so that the indexing engine can find the content that needs to be indexed . By default, the following locations are indexed for the local volume:

The Start menu (file:///%SystemDrive%\ProgramData\Microsoft\Windows\Start Menu) . The Users folder ((file:///%SystemDrive%\Users) and all user profile folders within it except for the Default user profile folder . (The AppData subfolder is excluded, however, for each user profile .) The Offline Files cache (Csc://{user s SID}) for all users who use the computer . (This indexing scope is used only if CSC is enabled on the computer .)

By default, all files and folders within these locations are indexed unless they are specifically excluded by a system exclusion rule as described previously .

panel. See the section Configuring the Index later in this chapter for more information. If Outlook 2007 is installed on the computer, this also appears as a default indexed location.

When Windows 7 is installed on a computer, the Windows Search engine configuration code performs the following steps:

1. 2. 3. 4. 5.

The Windows Search service is started . The system catalog is created (the first time) . The file, MAPI, and CSC protocol handlers are registered . Predefined system exclusion and inclusion rules are added (the first time) . Predefined start addresses are added (the first time) .

earch in Windows 7 and Windows Vista is language agnostic, but the accuracy of searches across languages may vary because of the tokenization of text

performed by features called wordbreakers. Wordbreakers implement the variable tokenization rules for languages. Wordbreakers will break down both the language of the indexed text and the query string; a mismatch between query and indexed language can cause unpredictable results. Windows ships with a well-defined set of wordbreakers and includes new tokenization code based on the Lexical Service platform (LSp) for some languages. For others, LSp will delegate to the class wordbreakers. If no wordbreaker is installed for a language, a neutral white-space breaker will be used. (Windows provides wordbreakers for 43 different languages.) at index time, the IFilter should determine the language of a property or chunk. If a file format does not encode language information, the language auto-detect logic is used to determine the language. at query time, the calling application (the shell, for example) designates the locale of the query.

Understanding how the indexing process works is helpful for troubleshooting issues regarding searching and indexing . The sections that follow outline different aspects of this process .

IFilters, property handlers, and the Windows property system are used to extract text from documents so that they can be indexed . Microsoft provides IFilters and property handlers for many common document formats by default, while installing other Microsoft applications may also install additional IFilters and property handlers to allow indexing of additional properties and content for documents created by these applications . In addition, third-party vendors may provide their own IFilters and property handlers for indexing proprietary document formats . IFilters and property handlers are selected on the basis of the file s extension . IFilters understand file formats, whereas property handlers typically just understand file properties . For example, files having the extension .t xt are scanned using the Plain Text filter, while files having the .doc extension are scanned using the Office filter and files having the .mp3 extension are scanned using the Audio property handler . All of these extensions are additionally scanned with the Windows property system to extract basic properties, such as file name and