If activation of Office over the internet fails, requiring to be activated by telephone, if it's an older version of Office you may receive error "Telephone activation is no longer supported for your product." This is not true. 

The number to call is: 866-421-7141, this is an automated system. Leave the activation prompt open as you will need to repeat an ID listed on the activation prompt to the automated system. After following through the automated system, Office should activate.