I think here is appropriate tread to ask this question: competition-for-the-best-gmat-error-log-template-86232.html
Usually, error log
is just a simple way to keep records of your answers and/or times for questions.
By the way, you may take a look how to use error log
in GMAT ToolKit for OG: http://www.youtube.com/watch?v=t0kCG4YQ77E
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