Can you boot up with the install media usually by tapping F12 as you switch on then use the cursor keys to select the media you are using - insert the media and press enter.
Navigate to the Install screen and select Repair your computer/Troubleshoot and select Command Prompt.
At the prompt enter bcdedit |find "osdevice"
For clarity that is a Pipe symbol before find and is the uppercase of \
Using your partition letter instead of the X I have exampled, enter these cmds -
dism /image:X:\ /cleanup-image /restorehealth
sfc /scannow /offbootdir=X:\ /offwindir=X:\Windows
Enter exit to close the cmd window, remove the install media and reboot to see if there is any change.
You may be able to perform the repair install now.
If you still get the Access Denied problem then download the Windows Repair program from -
www.tweaking.com and use it to boot into Safe Mode with Networking.
You can click on your WiFi icon if it works then click on your SSID and then on Connect, left click away to close the pane, otherwise you will need to Ethernet connect.
Open the repair program in that mode and select just the first five repairs which may be already default checked.
Reboot when done to see if you still get the Access Denied error when you double click on setup.
Let me know how you get on.