If you're using a Mac and getting an error similar to that below it's likely due to the fact that your Mac keyboard is not set to use straight single quotes.

The solution is simple. 

Step 1: Open your Application (Excel, etc.)

Step 2: From within your application go to Apple menu and open System Preferences

Step 3: Choose “Keyboard” and select the “Text” tab

Step 4: Pull down the submenus alongside “Double Quotes” and “Single Quotes” and select your preferred quote style for each.
You'll want to choose straight quotes.