I keep getting the following error however my button meets all of the requirements and works. 

• To pass this challenge, create a custom button which opens a link to 'http://google.com/#q={CONTACTNAME}' - where {CONTACTNAME} is the current contact's name. Then add this button to the default 'Contact Layout'.
• The custom button must be named 'Google Link'.
• The custom button must be added to the 'Contact Layout' page layout.

Challenge not yet complete... here's what's wrong:
There was an unexpected error while verifying this challenge. Usually this is due to some pre-existing configuration or code in the challenge Org. We recommend using a new Developer Edition (DE) to check this challenge. If you're using a new DE and seeing this error, please post to the developer forums and reference error id: SOLSGVKY