If you have Windows 8.1 and you cannnot install the Desktop e-mark Software, disabling the diver signature on Windows 8.1 may help.
Unlike previous versions of the Windows operating system, Windows 8 imposes strict limitations on driver signing. Because of this, unsigned drivers require extra steps for installation.
You will need to restart your computer several times throughout the course of these instructions. We recommend you print them before you begin, or use a separate computer to follow along.
What to do:
1- Hold down the Windows key on your keyboard and press the letter C to open the Charm menu, then click the gear icon (Settings).
2- Click More PC Settings.
3- Click General.
4- Under Advanced Startup, click Restart Now.
NOTE: In Windows 8.1, the 'Restart Now' button has moved to 'PC Setting -> Update & Recovery -> Recovery.'
5- After restarting, click Troubleshoot.
6- Click Advanced Options.
7- Click Windows Startup Settings.
8- Click Restart.
9- After restarting your computer a second time, choose Disable driver signature enforcement from the list by typing the number 7 on your keyboard.
Your computer will restart automatically.
10- After restarting, you will be able to install the Arduino drivers normally; however, Windows will display a warning message. When the warning appears, click Install this driver software anyway.
Note: The next time you restart your computer, driver signature enforcement will be in effect again. You will have to repeat this process for any new boards. If you have multiple boards to use with the same computer, we recommend installing the drivers for each one before you shut down or restart your computer.
Caution: Disabling your operating system's device signature verification can put your operating system at risk. You should only install drivers that you trust!