Adding file types for Search
By default only certain file types will be included when crawling content sources. Many common file types, such as PDFs, are not included so I’ve just added the PDF file type to my server. This is how:
1. Log on to Central Administration
2. Under Application Management click Manage Service Applications
3. Click the Search Service Application
4. In the Quick Launch, in the Crawling Section, click File Types
5. Click New File Type
6. Enter the relevant file extension and click OK
The next time a crawl is run the new file types will be included