I encounter the same problem whilst installing Office Professional Plus 2013: My MAP product key contains the letter "N", which is not accepted.
My Visio Professional 2013 license key also contains the letter "N" This was accepted?!
Refer to the article below to fix product key errors in Office:
Although written for Office2010, the same rules should apply;
When you read the product key from the label, certain characters may be mistaken for other characters. Here is a list of the most common mistaken characters:
Additionally, a Microsoft Office 2010 product key does not contain any of the following characters:
Make sure you type the right product key.
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