How can I get my product key

[LogicalRon]

I just built a new computer and I have to install Microsoft Office all my products that I buy are saved in my Outlook. My Microsoft account email  all of a sudden is getting this error message " The Microsoft account you've entered does not exist."  

Not sure how long it will take me to solve this issue with Microsoft and would like to have Ccleaner installed. How can I get my product key?

[nukecad]

If you still have ccleaner installed on another machine then look in Options>License key.

Or enter the email address that you used to purchase CCleaner into this page: https://www.ccleaner.com/support/license-lookup

Of course that won't work if you no longer have access to that email address.
In that case  you should email support@ccleaner.com from a different email account, they will want to know what that original email address was.

Or you could just use CCleaner free until you get your outlook back.