Customer says server lost email?

We have a customer who says that the server is not delivering all his email. He gave me an example of one email that one of his clients sent to him that he hasn't received (complete with date, estimated sent time and email address of the client). The email was supposedly sent last week.

What is the best way for me to check for this specific email? In the exim logs? What command would I use to find that specific date (like say January 3rd) and email address? (I'm still learing Linux)

And secondly, is it really possible that the server isn't delivering ALL email? My first gut instinct was that it went into his spam box but he says he doesn't have one. Where could those missed emails be going?

Any advice/tips would be greatly appreciated!

Thanks,
LAIG

 

 

 

 

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