My document title says [Compatibility Mode]

Cause: You opened a document that was created in an earlier version of Word.

Solution: Save the document in the .docx file format.
Solution: Work in compatibility mode.

Cause: The document was saved in the Word 97-2004 Document (.doc) format.

Solution: Save the document in the .docx file format.
Solution: Work in compatibility mode.

Cause: The document was saved with compatibility mode turned on.

Solution: Save the document with compatibility mode turned off.
Solution: Work in compatibility mode.