public void UnmarkAsException( 
   TopologyError error
)

// Get all the errors due to features violating the "PointProperlyInsideArea" topology rule.

using (TopologyDefinition topologyDefinition = topology.GetDefinition())
{
  TopologyRule pointProperlyInsideAreaRule = topologyDefinition.GetRules().First(rule => rule.RuleType == TopologyRuleType.PointProperlyInsideArea);

  ErrorDescription errorDescription = new ErrorDescription(topology.GetExtent())
  {
    TopologyRule = pointProperlyInsideAreaRule
  };

  IReadOnlyList<TopologyError> errorsDueToViolatingPointProperlyInsideAreaRule = topology.GetErrors(errorDescription);
  Console.WriteLine($"There are {errorsDueToViolatingPointProperlyInsideAreaRule.Count} feature violating the 'PointProperlyInsideArea' topology rule.");

  // Mark all errors from features violating the 'PointProperlyInsideArea' topology rule as exceptions.

  foreach (TopologyError error in errorsDueToViolatingPointProperlyInsideAreaRule)
  {
    topology.MarkAsException(error);
  }

  // Now verify all the errors from features violating the 'PointProperlyInsideArea' topology rule have indeed been
  // marked as exceptions.
  //
  // By default, ErrorDescription is initialized to ErrorType.ErrorAndException.  Here we want ErrorType.ErrorOnly.

  errorDescription = new ErrorDescription(topology.GetExtent())
  {
    ErrorType = ErrorType.ErrorOnly,
    TopologyRule = pointProperlyInsideAreaRule
  };

  IReadOnlyList<TopologyError> errorsAfterMarkedAsExceptions = topology.GetErrors(errorDescription);
  Console.WriteLine($"There are {errorsAfterMarkedAsExceptions.Count} feature violating the 'PointProperlyInsideArea' topology rule after all the errors have been marked as exceptions.");

  // Finally, reset all the exceptions as errors by unmarking them as exceptions.

  foreach (TopologyError error in errorsDueToViolatingPointProperlyInsideAreaRule)
  {
    topology.UnmarkAsException(error);
  }

  IReadOnlyList<TopologyError> errorsAfterUnmarkedAsExceptions = topology.GetErrors(errorDescription);
  Console.WriteLine($"There are {errorsAfterUnmarkedAsExceptions.Count} feature violating the 'PointProperlyInsideArea' topology rule after all the exceptions have been reset as errors.");
}