Have you successfully installed Office 2010 64-bit recently? Let us know in the comments how you handled the activation issue. Always back up your data before installing legacy software.
Looking for a "free" version of is a bit of a retro deep-dive, but there are a few interesting facts and modern alternatives to keep in mind. The "First" of Its Kind microsoft office 2010 64 bit free
Below are the pieces put together to help you install Office 2010 64-bit if you have a valid key, along with modern free alternatives if you do not. Have you successfully installed Office 2010 64-bit recently