I contacted him with his email in August and did not reply to his message.
Could it be he's not using he's email anymore or blocked me?
It's a private email not a gmail/hotmail email.
This is what the email says:
The address you sent your message to wasn't found at the destination domain. It might be misspelled or it might not exist. Try to fix the problem by doing one or more of the following: Send the message again, but before you do, delete and retype the address. If your email program automatically suggests an address to use, don't select it.
Clear the recipient AutoComplete cache in your email program by following the steps in this article: Status code 5.1.1. Then resend the message, but before you do, be sure to delete and retype the address.
Contact the recipient.
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