Trial Balance

Respond to the following in a minimum of 175 words: 

The mechanics of accounting involve analyzing the effect on the accounting equation of financial transactions. Knowing how transactions affect the accounting equation allows you to consider and account for all the ramifications of sometimes complicated transactions.

You are mentoring an accounting intern who asks for clarification about trial balances. She wants to know if a trial balance balances, would that guarantee that the trial balance is correct?

Consider her question. What possible errors could happen and still allow the trial balance to balance?