This blog post describes a workaround for an issue that I experienced while configuring email forwarding, specifically using godaddy webmail email forwarding to gmail addresses. This issue may apply to other configurations and providers. To summarize, it appears that if you forward through godaddy Workspace Webmail to a gmail address, google does not seem to deliver email that you send from that address through the forward. Try using a different email address to send the email.
I use a legacy godaddy email service called Workspace Email for email hosting and forwarding for my Internet domains. If I acquire a domain, I configure a forwarding address as a catchall that sends everything the domain receives to a gmail account. For example, email@example.com is a catchall address that forwards to my personal gmail address, meaning that firstname.lastname@example.org should forward to that address.
When testing this configuration, I found that if I send an email to an address on my domain (the forwarding account) from the same gmail address that should receive that forwarded email, then I do not receive the forwarded email. If I have configured an autoresponder for the forwarding address, then I do receive that response from godaddy, so I know the email is getting through to godaddy servers, but it does not forward to the gmail account.
Each time that I have encountered this issue, I have spent some time “troubleshooting” DNS and godaddy email settings, which is complicated by things like godaddy configuration change delays as well as DNS replication delays.
Recently, I found that if I send an email to the same address from a different address, even on gmail, then I receive the email. I did not spend any time investigating the cause of this issue or reporting it to google or godaddy. I do not have any explanation for why this seems to work, but I consider it to be a suitable workaround.