This is an error related to email.
If you write to an address that doesn't exist, you'll receive a bounce message saying "550 No Such User Here", which means this user doesn't exist.
This error does not indicate any problem with your hosting service. It's an informational email that tells you the email address you're writing to doesn't exist.
Most likely, it existed in the past but for some reason the domain administrator deleted it.
Variants of the error
This error can appear with different messages — the most common are:
- no such user here
- no such user here sender verify failed
- no such recipient here
- no such mailbox
- no such recipient
- no such user here (in reply to rcpt to command)
- error 550
- smtp 550