"You must accept the Office End User License Agreement" message when starting Office programs.
Problem
Every time you start a Microsoft Office program like PowerPoint, Word or Excel, you must accept the Office End User License Agreement (EULA) before the program is allowed to start.
When you agree to the EULA and accept it, the Office program starts up and you can use it normally, but the same thing happens every time you start any Office program.
This applies to any version of office from 2000 onward.
Solution
Log in to Windows as an administrator or run the Office with administrator credentials. When you see the EULA screen, click I accept. Repeat for any other Office programs that show the EULA at startup.
If you need a more detailed explanation, you'll find more information in Microsoft's Knowledgebase Article 884202