Is it possible to change the attached file?

Question

Email

The bottom line is that I sent a letter to the customer by mail from a working computer with an attached file. When I arrived at his office, it turned out that the attached file did not contain the data that I sent, checked those sent from the phone, but not the ones. When I arrived, I opened the sent letter from the computer, everything is fine, the files are . how can it be. I’m sitting here I can’t understand ten times in turn I open the same letter from a mobile phone, then from a computer, different files, the time of departure and the addressee are the same.

Answer 1

1. Is this information a diagram of the drawings of the Death Star? Believe me, with a probability of 99.999%, no one needs your correspondence with the customer and, of course, no one has replaced the file.
2. Most likely, somewhere you have something cached / not preserved, etc.
3. If paranoia torments you too much, then encrypt s / mime or pgp correspondence in the future, and additionally archive the attached file in zip with a password :)