Please also refer to the following articles.
What to do when email transmission failed (troubleshooting)
- Is the email sorted into the spam folder?
- Is the sender's email an SPF-certified email?
- Have you reached your email-sending limit?
- About inquiry
Is the email sorted into the spam folder?
Forwarded emails are often treated as spam.
Also, depending on the e-mail software used to receive the e-mail, even if there is an e-mail in the spam folder, notifications such as the new arrival mark may not be displayed.
I'm sorry to trouble you, but could you actually open the spam folder and check it?
Is the sender's email an SPF-certified email?
When forwarding an email that has received SPF authentication, an error may occur and the forwarding may fail.
Please disable the SPF function in the sender's email settings, or change the SPF record to allow forwarding with the SPF function enabled.
*For SPF records, we cannot guide you because the information to be set differs depending on the settings of the sender.
Related information (external link)
[Solution to the problem of compatibility between SPF and forwarding: Anti-Spam Committee]
Have you reached your email-sending limit?
Email sending limits also apply to forwarding. If you see an error message like the one below, you have reached the upper limit of the email-sending limit set for each account.
Domain example.com has exceeded the max emails per hour (2/1 (200%)) allowed.
Please refer to the following page for details on sending email restrictions.
Email sending limit
About inquiry
When inquiring about the fact that the mail cannot be forwarded, could you please provide the following information?
- sender email address
- forwarding intermediate email address
- inbound email address
- Email sent time
- If a return email or error message is displayed, its contents