Early 2008 we have posted a blog entry with a VB script that generates some pre-canned reports that are based on message tracking logs. The script has proven to be useful in understanding Microsoft...
Published Jan 21, 2010
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@JohnB, what you are noticing is unusual, the only case that I can think of where this can happen, is if you have enabled the analyzers that re-write the logs (e.g. smtp session formatter, smtp session separator, etc).
What analyzers do you have enabled?
What analyzers do you have enabled?