I created 2 chars, 1 miner & 1 hauler.
Once my miner got the mining laser upgrade, I sent the old minig laser to my hauler, to check a few features.
However, although the game told me that the email was sent, my alt never received it.
There was no possible mistake on my end for recipient name.
When items are attached to mail, they take 1 hour to arrive, as described on the mailbox screen in orange:
My mistake, I was paying attention to the mail fields and did not notice this 
no problem at all, I would rather have 100 reports that are not bugs, than miss one that is 