I'm not sure if this will work for you... Your Mileage May Vary, but...
I just upgraded to Windows 10, and had the same issue, I was unable to install Samsung Easy Settings on my Series 7 laptop, so no Fn+Keys working.
So what I have been able to determine is that the only reason it won't run in Win10 (and probably 8/8.1 as well) is that the digital signature was revoked by Samsung. Huh??? Windows won't run it because the signature is invalid. The solution was to strip the signature from the .exe file, and then it ran!
Here's how I ended up working around it:
1. Download the Easy Settings app from Samsung (It came in a .zip file for me) and extract it
2. Download FileUnsigner (http://www.fluxbytes.com/software-releases/fileunsigner-v1-0/ - or Google it... with Bing!) and extract the executable
3. Drag the setup.exe from the Easy Settings folder onto FileUnsigner.exe. You should see a message saying success.
4. Windows UAC will now NOT complain, but guess what... Windows 10 now says Easy Settings is incompatible and will still refuse to run it!
5. Rename setup.exe to anything else (setup2.exe worked for me)
6. Run setup2.exe, install as usual.
7. When Setup is complete, browse to the install location (C:\Program Files (x86)\Samsung\Easy Settings for me)
8. Move ControlCenter.exe to your desktop (or anywhere you have write-permission)
9. Remove invalid signature from ControlCenter.exe by dragging that onto FileUnsigner.exe
10. Move ControlCenter.exe back to the install directory
11. Right-click ControlCenter.exe, go to Compatibility, and set compatibility mode for Windows 7
12. Run ControlCenter.exe. You should have a working Easy Settings app and working Fn+Keys.
Note: You may need to enable sideloading of apps for this to work. I had already done that, so I don't know if it affects the process or not.
Hopefully, Samsung will get their act together soon so we can have a working, properly signed settings app for our shiny laptops, without having to jump through all these hoops...
Windows 10, version 1511 has been released, and is actively removing Samsung's Easy Settings during the upgrade. I found that i could reinstall it afterwards just by renaming the installer .exe from Setup.exe to SomethingElse.exe, and it installed just fine. However, Nothing Worked™ and i had to do more digging. So far i have some of the hotkeys back to working, but no Easy Settings.
Samsung is adamant that this laptop doesn't support Win10, and MS is adamant that everything runs Win10. My attempts to contact Samsung just result in replies that drivers dont work in 10, and links to newer laptops that are officially supported.
I'm so fed up with their lack of interest that I'm currently reverse engineering their hotkey program to make one that works, and so far what I've found is that they are just too lazy to change a few things and recompile it to work in 10. All to try to sell me an "upgrade" to a perfectly good laptop.
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