I have installed Quartus 18.1 Standard Edition and the required Cyclone V files from the Intel download center.
When I open a new project via project wizard there are no devices shown at all.
would appreciate any help,
Thanks in advance!
Just to clarify; you've downloaded the Cyclone V device support file right? Did you verify that your operating system (OS) is correct when you downloaded the files?
After downloading the support files, you need to install the device on Quartus. To do this, go to Tools>Install Devices..
Then, follow the steps in the installer to install the device support.
Note: If you do not see the Install Devices command, you can access the device installer from the Start Menu of your computer.
Additionally, you can refer our Quick Start Guide here. The device support installation guide is at the last page: https://fpgasoftware.intel.com/static/quick_start_guide/quick_start_guide_18.1_en.pdf
Let me know if this helps.
I'd just try uninstalling and reinstalling. You might just have a bad installation. If you have the Cyclone V .qdz file in the same directory as the Quartus installer, you can install the software and devices at the same time, which should guarantee that it will work.