Office for the Mac - file open slowness, freeze, or crash

Question

When I select the File - Open window, any of the Office programs take a few minutes to display all of my files in the Documents folder. When they are finally displayed, any attempt to scroll through the list or go to a specific file results in the Mac's spinning wheel being displayed. Quite often, nothing happens after the wheel stops spinning. Sometimes, it just continues to spin. Consequently, it is almost impossible to use the File - Open window in Office to select a file to open. The only way I can do so is to use Finder to display my files in the Documents folder and then selecting them in that program's File - Open window.
When the wheel is spinning, Force Quit says that the specific Office program being used is "not responding." Usually, I use Force Quit to close down the Office program if it has frozen, crashed, or been slow using the File Open window.
I spent an hour yesterday with Microsoft Support on the problem. The conclusion of the tech was that I had too many files in my Documents folder. I pointed out that other programs such as FileMaker Pro didn't have this problem. The tech's response was that Office has to scan the entire Documents folder every time the File Open window is opened, but that FileMaker Pro stores a list of the last files in the Documents folder and doesn't rebuild the list every time.
I am skeptical of this "answer." The problem didn't exist until a few months ago.
My computer is a MacBook Pro 2.3gHz with 16 GB of RAM and a 750GB hard drive which has about 500GB free. This is a fairly fast machine with a Geekspeed of 10688. I was running the latest Mac OS Yosemite 10.10.1. The problem first surfaced with Office for the Mac 2008 about 3-4 months ago running Mac OS 10.10.1. I installed Office 365 yesterday, and and Mac OS Yosemite 10.10.2 today, and nothing changed.
The only solution that I know of is to take a lot of time to segregate my files in the Documents folder into more subfolders (I already have quite a few). That I am loath to do, because the solution doesn't work very well. It takes about a minute to select a subfolder in the File Open window, and then about another 30 seconds before Office allows me to scroll through a relatively small number of files (e.g., 100 files) in the subfolder.
When this question was posted to the Microsoft Community, I was directed to an article talking about problems with Office and Mac OS. None of the solutions worked, probably because the article considered only Office X and Office 2004 for the Mac and OS 10.2 and 10.3.
Help, please!

Answer 1

1) Verify that Office is fully updated. v14.4.7
2) I suggest you run Font Book and vailidate your Fonts. Microsoft installs duplicate fonts and after you clean up your fonts, this has often fixed odd issues with Office.
Office 2011 Duplicate Fonts to Delete
3) Delete the com.apple.LaunchServices file in your User's Library/Preferences folder. Log out under the Apple in the Menu bar and test. More info
If this fails to fix....
Testing in a new User will quickly tell you if the problem is system wide or if it's your User's folder that contains the problem.
Put a few test files in the Shared folder. Data in the Shared folder can be accessed by another User. When you "Switch Users", you can access the files in the shared folder. After you log into the new test User, drag from Shared (it actually copies). Put the test files in Documents.
Open Word. It won’t be in the Dock in the new User. Go to Applications to open.
Do you still see the issue?
If yes, you can eliminate the number of files in your Documents folder.
If no, then you might want to do a clean up in Documents.
*Remember to drag files back from Shared when you log into your main User.
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