Windows 7: Search does not find files that it should, directory is indexed, and *.php included on the extension list

Correction:  (3) above should read:

... "system.filename:~=converter AND ext:.exe" ...

The search not working is what actually brought me here...or conversely, the computer changed it's behavior and I'm not able to adapt.  I honestly believe the search is working but something else is causing it to appear broken.  I still need help though.

For my job I receive POs as tif files.  I open them and "save a copy" to a folder - renaming them as 'company name - PO number'.  Later I email my copy of that PO.tif by clicking "attach" and pasting the PO# in the search box.  Pasting "just" the PO# always provided the exact PO I needed.  That worked fine until recently.

On May 9th I upgraded from Office 2007 to 2010 and installed the Office 2010 patches.  After that I got no results when pasting the PO number in the explorer search box.  I am trying things as I type this and have noticed the following:

• Clicking the start button and pasting the PO# there finds the file - in email and in the file folder.  This indicates the search function is working, but why not with file explorer?
• Using file explorer only finds POs (TIFs) from before May 9th but not after.
• file explorer finds PDFs and spreadsheets before and after May 9th using partial names and wildcards needed.  Example, for the file name "Microsoft Details" I can type "details" or " *tails" and file explore finds the files.  But if I type "tails" without the * wildcard nothing is found...that's all good.
• PDFs and spreadsheets appear to have their properties searched too but not their contents.
• TIFs by default open with "Windows Photo Viewer", which is what I've been using for years.  Today I tried opening a TIF with Office 2010 and then saved a it to the PO folder just like before. File explorer found that PO (same TIF name) just fine.
• The above got my attention so I tried several things.  Instead of opening TIFs from an email I copied them to another folder, then opened them from that folder with Windows Photo Viewer and saved the file to my PO folder.  Still not found in a search.
• Next I tried to open an older TIF (pre-May 9th) and resave it but I couldn't because the original was read-only.  I noticed everything was read-only beginning May 9th.
• Neither removing the read-only flag nor saving it without read-only changed anything.  TIFs after May 9th still weren't searchable.
• Opening a TIF with Windows Photo Viewer and resaving it with a completely different name only worked when the original file was created before May 9th.  Even though I renamed and saved the file today, the Date Modified showing in file explorer was still the old date.
• Repeating the above step but using Office 2010 to open and save the TIF worked fine.  The new file was searchable and the "Date Modified" in file explorer showed today's date and time.  I'm not sure if the date/time stamp is relevant but thought its worth mentioning.

I started this post thinking it was a Search Index issue but its looking more and more like "Windows Photo Viewer" was somehow modified when I upgraded from Office 2007 to Office 2010.  I posted this here because I don't know if the Search Index can't find certain new TIFs or if Windows Photo Viewer is preventing its TIFs from being found.  I suspect others might be experiencing similar things.  As a user I thought I was just upgrading Office - no other changes were wanted.  This is the type of thing that drives me crazy.

I read and read, and rebuilt the index several times.  After wasting all that time I now have to start over and see if anyone knows how to fix Windows Photo Viewer...if that's really the problem.

A couple more notes on getting Search working:

1. If you use File Explorer and go into View | Options | Change folder and search options, then select the Search tab, there is a check-box (second one down) to select "Don't use the index when searching in file folders for system files (searches might take longer)".  For some obscure reason (this is on Windows 8, not sure about Windows 7),checking or unchecking this box produces different search behaviour even for the non-system files.  If you are having difficulty, changing this option could be worth trying.
2. Someone may already have mentioned this, but the security properties on the folders/files you want indexed must include the SYSTEM group name (to which I gave Full Permissions).  I was wondering why nothing I searched for in my libraries would turn up, and the reason turned out to be that somehow the SYSTEM group had been removed from all the "My ..." folders.
3. @Brian100:  For the contents of PDF files to be indexed, you either have to have installed Adobe Reader (32-bit system) or the Adobe 64-bit IFilter (see above for details) for 64-bit Windows.  Also you need to check in Indexing Options | Advanced | File Types that PDF files have the Filter Description "PDF Filter".  Also, note that only about the first 8 MB of a PDF are indexed, although Microsoft don't document this anywhere (that's roughly the first 800-900 pages of a document).
4. @Brian100:  Using Microsoft Office 2010, I tried sending myself some test e-mails (to and from different e-mail addresses) with TIFF files attached.  Once Search had had time to index the files, I had no problem finding them or the relevant e-mails.  I haven't had any problem with files saved from Windows Photo Viewer either.  So I don't have any real solution for you, I'm afraid.  I know this is extreme, but you would probably find your problems went away if you reinstalled Windows (ouch!).  It's for situations like this that I maintain two system backups on an external drive (using EaseUS ToDo), one taken just after installation of Windows and basic applications (e.g. Microsoft Office), and one recent.  Then it only takes an hour or so to regain a good system, much quicker and easier than reinstalling from scratch.  Data is on a different partition, so is unaffected.

Good luck!

Just a simple question from a simple mind...IS MS KIDDING WITH THIS THING?? A File Manager system that refuses to let you work on files. You have to go through the windows Library system to get to your files. You have to use the search command to find your files, and then the search command will not find the file you are looking for. It will find the type of file that Bill Gates THINKS you should be looking for. I did a search on a movie..This is an AVI file... Called "The Image" so what comes up? Every DAM jpg & gif file on the system. Never did find the movie. ;( As bad jokes go this is not that funny; as an OS it is a great advertisement for Linux. ;(