How to enable PDF search in Windows (64-bit)
Modern operating systems have the PDF search functionality already built-in, so you won't need a third party tool to search PDFs - the operating system will do it for you. However if you are not able to search the PDF files, you may need to edit your Windows settings and/or install the iFilter plug-in.
The iFilter plug-in usually gets automatically installed when you install a PDF reader software (such as Adobe Reader) on 32-bit Windows. However the iFilter plug-in does not install automatically on any version of 64-bit Windows.
To find out what version of Windows is installed on your workstation, click Start, right-click Computer, click Properties and see the System type information (an example screenshot is shown below).
If you have a 64-bit version of Windows installed, you would now have to go to the Control Panel, open Indexing Options and then click the Advanced button. Then on the File Types tab check that "pdf" is shown on the list. If Filter Description states "Registred IFilter is not found" you will need to install the iFilter plug-in manually. At the moment of writing this article the latest version of iFilter for 64-bit Windows is 11. You can download it from Adobe's web site and install it.
When iFilter is successfully installed the Filter Description will state "PDF filter" which means that Windows can now index PDF files. If you additionally wish to index the content of the PDF documents (and not just the document properties) you will need to un-check the "Index Properties Only" option and check "Index Properties and File Contents" option instead (see below screenshot).
When all of this is done it is also a good idea to rebuild the index in order to make sure that the existing PDF files are indexed correctly. Go back to Index Setting tab and hit the Rebuild button.
Note: In order to search PDF attachments as well, an iFilter should be installed which supports indexing of PDF attachments. Several commercial alternatives are available on the web.