"application has been blocked from accessing graphics hardware"

I had the same issue with my PC and it turned out to be the application software that was the issue. Try installing the driver withour installing any Nvidia or AMD software. 

How is the result?

READ IT !! I FIXED IT FOR NVIDIA DRIVERS !!

I have nVidia GTX 580

The problem that Causes the Applications to be blocked from your graphics hardware is that you have wrong overclocking settings and by wrong i mean Unbalanced for example

For MSI nVidia & Radeon

1. Put your voltage ( Core Voltage to 1.1mV or 1100mV for after burner)

now my factory Settings are:

1000mV core voltage

Core clock (MHz) 795

Shader Clock (MHz)1590

Memory Clock (MHz) 2004

So basically my over clocking must be:

core voltage = 1100

Core clock (MHz) = 900

Shader Clock (MHz) = 1800

Memory Clock (MHz)= 2225

BUT NO !!! this is unstable !!! 900 Core clock and 1800 Shader clock needs more Voltage and more memory clock and that makes your GPU rejecting shaders because it holds more that it can read !!!

SO FOR THE FIX !!!

1. Re-install Fresh drivers from here:

http://www.nvidia.com/Download/index.aspx?lang=en-us

2. Uninstall MSI After burner and any other overclocking software and Re-install fresh one.

for MSI After Burner here:

download.msi.com/uti_exe/vga/MSIAfterburnerSetup.zip

3. Put balanced settings depending on the GPU you have, For example:

i have Memory Clock (MHz) 2004 that means i need 1075 Core voltage so

i Put my Core voltage 1100 and Memory clock 2225 stable but, more MHz in memory need more reading that means i need balance Shader with the memory clock so instead of 1590 or 1800 i prefer 1650, remember Core clock and Memory clock must be apart on 1/3.

HERE IS MY SETTINGS

core voltage (mV) = 1100

Core clock (MHz) = 825

Shader Clock (MHz) = 1650

Memory Clock (MHz)= 2225

Tips

every 125 Core clock you need 0.100 (mV)

every 1000 Memory clock you need 0.100(mV)

READ IT !! I FIXED IT FOR NVIDIA DRIVERS !!

I have nVidia GTX 580

The problem that Causes the Applications to be blocked from your graphics hardware is that you have wrong overclocking settings and by wrong i mean Unbalanced for example

For MSI nVidia & Radeon

1. Put your voltage ( Core Voltage to 1.1mV or 1100mV for after burner)

now my factory Settings are:

1000mV core voltage

Core clock (MHz) 795

Shader Clock (MHz)1590

Memory Clock (MHz) 2004

So basically my over clocking must be:

core voltage = 1100

Core clock (MHz) = 900

Shader Clock (MHz) = 1800

Memory Clock (MHz)= 2225

BUT NO !!! this is unstable !!! 900 Core clock and 1800 Shader clock needs more Voltage and more memory clock and that makes your GPU rejecting shaders because it holds more that it can read !!!

SO FOR THE FIX !!!

1. Re-install Fresh drivers from here:

http://www.nvidia.com/Download/index.aspx?lang=en-us

2. Uninstall MSI After burner and any other overclocking software and Re-install fresh one.

for MSI After Burner here:

download.msi.com/uti_exe/vga/MSIAfterburnerSetup.zip

3. Put balanced settings depending on the GPU you have, For example:

i have Memory Clock (MHz) 2004 that means i need 1075 Core voltage so

i Put my Core voltage 1100 and Memory clock 2225 stable but, more MHz in memory need more reading that means i need balance Shader with the memory clock so instead of 1590 or 1800 i prefer 1650, remember Core clock and Memory clock must be apart on 1/3.

HERE IS MY SETTINGS

core voltage (mV) = 1100

Core clock (MHz) = 825

Shader Clock (MHz) = 1650

Memory Clock (MHz)= 2225

Tips

every 125 Core clock you need 0.100 (mV)

every 1000 Memory clock you need 0.100(mV)

Glad this works for you 

But doesn't resolve the issue, have tried your fix exactly as you describe on my system 

Msi GT70 (factory built laptop) 

Upgraded to windows 10, and bam no more gpu. 

You'd think F**#ing microsoft would have looked into making this Application access *feature*??(haha) actually work correctly.

This post is from '13 on win 8.. the problem still persists.. 

How the F**# hasn't this been fixed? 

Ubuntu works great windows 7 works in my case. but still M$ fix your Sh*t. 

//rant

Hmm... try to increase the mV to 1100 if this doesn't work try lowering the GPUs Core clock (MHz)

every time you get this message keep lowering it by -50 until it stops giving you the problem i was in 1225 and i end it up on 850, i don't get the message now and i play fine.

here is my skype if you need farther assistance (Ravenrosail)