I played Holmes The Testament on my old computer Windows 7 and it was fine,no problem.I now have another computer Windows 8.1 and after downloading the entire game from Amazon when I click, it wont play.I didn't get the option to enter the activation #I cant figure it out.Maybe someone knows something please.

to GameBoomers. I am not familiar with Amazon downloads, but hopefully someone here will have some suggestions/advice to offer you.

That actually sounds like it hasn't even installed.

But assuming it did install, if you Google
Windows 8.1 Sherlock Holmes Testament won't start
you'll find that people with the Steam version also had a problem with the game not starting, both with Windows 7 and with Windows 8.1, and there are various fixes suggested.

One has to do with disabling an antivirus that's blocking activation.

Another is to run the game as adminstrator (right-click the Shortcut and then Run as Administrator).

Another is to install PhysX-9.13.1220-SystemSoftware.msi package, then install PhysX-9.13.0604-SystemSoftware-Legacy.msi

You can also try contacting the developer at
http://frogwares.com/support/

I'm trying to remember if I had to install the games I downloaded from Amazon. After the download completed, did it tell you it was installing and then place a game icon on your desktop?

Yes after download was completed,there was a game icon on my desktop

I have never downloaded a game from Amazon so this is just a Stab in the Dark:
Is it possible that since you already installed the game on your Win7 machine that it will not work on any other machine because of the "Activation Code will only work once"?

I've downloaded my Amazon games several times and there has never been a problem. I will try one on my Windows 7 drive tomorrow.

If you right click on that game icon and select properties, what does it say in the "target" box?

I uninstalled it and I'll try again with some of the help I've received from you all.Thanks a lot .

I installed the game again and clicked the desktop icon and chose administer,then typed in the code and the game is playing fine.I have a problem with the magnifying glass.I was able to use it to inspect the broken glass,and the music sheets on the floor,but then it disappears.What am I doing wrong?

Marita's walkthrough describes controls near the beginning.
http://www.gameboomers.com/wtcheats/pcSs/SH6/SH6.htm

So try the space bar.
If that's not the problem, look at the controls menu.
It's possible you have to be in a certain "mode" for the interaction to work. I haven't played the game recently and don't remember.