Word can check certain aspects of a document as you are working on it. For example, Word can check your document for spelling and grammar errors. Word underlines any inconsistencies with a red (spelling) or green (grammar) wavy line.

Word can also check your document for formatting inconsistencies and underline them with a blue wavy line. This functionality was introduced on Word 2002.

To configure Word 2007 to mark formatting inconsistencies:

• Click the Office button and then click Word Options.
• Click Advanced.
• In the Editing Options section, make sure the Keep Track of Formatting check box is selected.
• Make sure the Mark Formatting Inconsistencies check box is selected.
• Click OK.