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I'd like to use Windows Search for searching through multiple PDFs in one go, but I see that in the Indexing Options' Advanced Options screen, PDF files don't have a registered IFilter: Registered IFilter is not found

What is an IFilter, and where can I get the appropriate one?

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4 Answers 4

up vote 15 down vote accepted

IFilters allow Windows Search to search within file contents.

Here are three popular PDF IFilters. They are ordered by search performance according to this article:

  1. Foxit PDF IFilter (commercial, fastest)
  2. TET PDF IFilter (free/commercial, fast)
  3. Adobe PDF IFilter (32-bit / 64-bit) (free, slow)

After installing one, you should be able to search within PDF files in the same way that you can for other types of files.

PDF Filter

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I tried this but it did not work for me. I'm on Windows 7 Professional (64-bit), with Adobe Reader X. I installed the iFilter, added it to my PATH environment variable, restarted my computer, and waiting until Windows was indexing, but I still couldn't search within my PDFs. I did have to install under my PC's administrator account, which is a different user, I wonder if that affected it. –  M. Dudley Jul 2 '12 at 17:03
Did Windows finish indexing? –  Louis Jul 2 '12 at 19:52
@emddudley, if you want the PDF contents to be indexed, you should ensure that in the above screenshot, "Index Properties and File Contents" is selected for PDF files. Also, if you're searching non-indexed files, you may have to prefix your search query with content:. –  Sam Jan 17 '13 at 23:41
The above referenced MSDN article that @Louis refers to is actually talking about the speed of the content indexing. This is the speed at which the Windows Search (or Search Server) crawls through the content and adds it to its data. The speed of the search is not affected at all and is the same regardless of IFilter used. So unless you are needing to index a large number of new files quickly, the speed of the indexing probably does not matter for most people. –  dmarietta Dec 30 '13 at 20:43

An alternative way to search through PDFs is to use the search function of PDF-Viewer. It does not need indexing neither. This is my choice.

Search PDF in PDF-Viewer

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Thanks, I didn't know this feature existed in the standard Reader. Sure is dang slow though. –  I. J. Kennedy Dec 26 '13 at 18:20
+1! Didn't know this. PDF-XChange Viewer is just awesome. Surprises me all the time. –  Bloke Aug 30 '14 at 21:04

PDF XChange Viewer, which has a free version available, comes with a built-in iFilter.

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You can sort, filter pdf files based on title, pages etc using this shell extenion Debenu

Additionally, this portable application extracts all data from pdf files and produces a tabluar output which you can use in your workflow pdfinfogui

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Are you affiliated with Debenu? –  slhck Dec 31 '13 at 8:25
No. I was facing a similar issue and had tried both the softwares. So, thought I will share the info. –  S Rahul Bose Dec 31 '13 at 12:10

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