Related Clues:

• Say 2 + 2 = 5, say
• Certain computer message
• Prove one's humanity
• Transgress
• Make mistakes
•     Drop a brick
• Make a faux pas
• Make missteps
• Failing
• Boot one
• 2 + 2 = 5, e.g.
• Slip or trip, e.g.
• Be incorrect
• Be in the wrong
• Typo, for one