Is Email Forwarding (i.e. from Google Domains or Namecheap) Reliable?

audelair · 10 Aug 2017, 07:17 AM

Hello,
I have a couple domains hosted by Google Domains, which offers free email forwarding. I was wondering if email forwarding used in this fashion is as reliable as having a dedicated email service with a mailbox?

I am not worried about sending FROM the addresses (I have SMTP options available for these domains should I need it), but merely want to make sure emails delivered to me are forwarded as reliably as it would if emailed directly to a mailbox?

I understand that automatic forwarding is not something that someone wants to set up themselves. It can get your IP blocked if too much spam gets forwarded. But I was wondering if some of these big providers like Google and Namecheap can properly implement email forwarding reliably?

Thanks!

jeffpan · 10 Aug 2017, 11:38 AM

don't trust forwarding even you have SPF/DK setup and the forwarding provider has SRS setup.

n5bb · 10 Aug 2017, 12:35 PM

The problem isn't necessarily the forwarder. Many email systems may block (or mark as likely spam) messages which are not sent by the SMTP servers specified in the SPF and DMARC DNS records for the sending domain.

Everyone is tired of spam. So there are now email standards (SPF, DKIM, and DMARC) which allow sending domains to specify which SMTP senders are allowed to send messages directly to the destination server and how to verify an encryption tag in the header which indicates if the message was signed by a sender at that domain and not modified in transit. To show you why this is important, please look at the following DMARC testing website:
https://dmarcian.com/dmarc-inspector/
Enter a domain in the DMARC Inspector field at the left and then click Inspect The Domain. For some popular domains (such as both yahoo.com and aol.com) the DMARC policy is p=reject. This means that those domains strongly suggest to any email system receiving mail with From at that domain to check the following:

Header From should match Envelope-From. This means that the SMTP server sending the message to the final recipient needs to identify the SMTP From address the same as the header From address.
The final SMTP server sending the message to the final destination should have an IP address that matches the SPF DNS records for the sending domain.
The message should be DKIM signed with an encrypted tag which matches the DNS records for the sending domain.
At least one of the SPF or DKIM test must match to pass the DMARC authentication test.
Forwarding by a good forwarding service should not corrupt the DKIM test, so theoretically even a reject DMARC policy should not cause a good message to be rejected.
But forwarding will cause the DMARC SPF test to fail. So any failure of DKIM will cause the message to be rejected if the policy is p=reject and the message is forwarded. This is also sensitive to the DMARC address alignment rules, which allow the sender domain DNS entries to control how the envelope-From and header From are compared with regards to the exact domain (and subdomains).

So forwarding stresses the DMARC test. The details of message rejection is controlled by the sending domain and the final delivery email system.

Bill

audelair · 11 Aug 2017, 04:35 AM

Interesting.
Looks like email forwarding is not what it used to be. I used to forward my alumni address to me until I stopped getting them reliably over the past few years. Luckily, my University switched over to GSuite for Education and all alumni's have an account now, which allows me to POP3 it over to my personal account, which is failproof.

This is great info to know, and I will cease forwarding accounts and start using proper mailboxes. Thanks!

TenFour · 11 Aug 2017, 05:20 AM

Despite the known issues, I have found that forwarding via Outlook.com and POBox.com to Gmail is very reliable. I also have forwarding via some domain services at low volume, but I have yet to miss a message that I know of. I recently ran a check to see if any messages forwarded from Outlook.com to Gmail were missing and they had all been forwarded. I'm using POBox.com's Basic level (just forwarding, no mailbox) as my main email service and so far it has been reliable.

10 Aug 2017, 07:17 AM	#1
audelair Essential Contributor Join Date: Feb 2004 Posts: 271	Is Email Forwarding (i.e. from Google Domains or Namecheap) Reliable? Hello, I have a couple domains hosted by Google Domains, which offers free email forwarding. I was wondering if email forwarding used in this fashion is as reliable as having a dedicated email service with a mailbox? I am not worried about sending FROM the addresses (I have SMTP options available for these domains should I need it), but merely want to make sure emails delivered to me are forwarded as reliably as it would if emailed directly to a mailbox? I understand that automatic forwarding is not something that someone wants to set up themselves. It can get your IP blocked if too much spam gets forwarded. But I was wondering if some of these big providers like Google and Namecheap can properly implement email forwarding reliably? Thanks!

10 Aug 2017, 12:35 PM	#3
n5bb Intergalactic Postmaster Join Date: May 2004 Location: Irving, Texas Posts: 8,927	The problem isn't necessarily the forwarder. Many email systems may block (or mark as likely spam) messages which are not sent by the SMTP servers specified in the SPF and DMARC DNS records for the sending domain. Everyone is tired of spam. So there are now email standards (SPF, DKIM, and DMARC) which allow sending domains to specify which SMTP senders are allowed to send messages directly to the destination server and how to verify an encryption tag in the header which indicates if the message was signed by a sender at that domain and not modified in transit. To show you why this is important, please look at the following DMARC testing website: https://dmarcian.com/dmarc-inspector/ Enter a domain in the DMARC Inspector field at the left and then click Inspect The Domain. For some popular domains (such as both yahoo.com and aol.com) the DMARC policy is p=reject. This means that those domains strongly suggest to any email system receiving mail with From at that domain to check the following: Header From should match Envelope-From. This means that the SMTP server sending the message to the final recipient needs to identify the SMTP From address the same as the header From address. The final SMTP server sending the message to the final destination should have an IP address that matches the SPF DNS records for the sending domain. The message should be DKIM signed with an encrypted tag which matches the DNS records for the sending domain. At least one of the SPF or DKIM test must match to pass the DMARC authentication test. Forwarding by a good forwarding service should not corrupt the DKIM test, so theoretically even a reject DMARC policy should not cause a good message to be rejected. But forwarding will cause the DMARC SPF test to fail. So any failure of DKIM will cause the message to be rejected if the policy is p=reject and the message is forwarded. This is also sensitive to the DMARC address alignment rules, which allow the sender domain DNS entries to control how the envelope-From and header From are compared with regards to the exact domain (and subdomains). So forwarding stresses the DMARC test. The details of message rejection is controlled by the sending domain and the final delivery email system. Bill

10 Aug 2017, 11:38 AM	#2
jeffpan The "e" in e-mail Join Date: Sep 2005 Location: Macao Posts: 2,137 Representative of: tls-mail.com	don't trust forwarding even you have SPF/DK setup and the forwarding provider has SRS setup.

11 Aug 2017, 04:35 AM	#4
audelair Essential Contributor Join Date: Feb 2004 Posts: 271	Interesting. Looks like email forwarding is not what it used to be. I used to forward my alumni address to me until I stopped getting them reliably over the past few years. Luckily, my University switched over to GSuite for Education and all alumni's have an account now, which allows me to POP3 it over to my personal account, which is failproof. This is great info to know, and I will cease forwarding accounts and start using proper mailboxes. Thanks!

11 Aug 2017, 05:20 AM	#5
TenFour Master of the @ Join Date: Feb 2017 Location: USA Posts: 1,731	Despite the known issues, I have found that forwarding via Outlook.com and POBox.com to Gmail is very reliable. I also have forwarding via some domain services at low volume, but I have yet to miss a message that I know of. I recently ran a check to see if any messages forwarded from Outlook.com to Gmail were missing and they had all been forwarded. I'm using POBox.com's Basic level (just forwarding, no mailbox) as my main email service and so far it has been reliable.