Read this article : Find your product key for Office 2013 and Office 365 suites. It may solve your problem.
I just recently purchased a Dell Inspiron 15 and I like it.  I am just not very smart when it comes to technology and need some help.  I just spent $100 on a year subscription to Microsoft Office 365.  Sometimes when I try to open it, it says enter in your product key, which I have never received.  Other times, It says "unable to install because of missing or corrupt files.  Contact computer manufacturer."     Any suggestions on what I can do?
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