Deliverability to web.de

Emails Sent to web.de: 1,449,096

Open Rate to web.de: 118,854 (8.2%)

Date range:
Display as:

Sent vs Opens for web.de

Date Sent Opens Open Rate
9/3/2020 1,406 127 0.0%
9/2/2020 949 118 0.0%
9/1/2020 1,069 154 0.0%
8/31/2020 1,127 138 0.0%
8/30/2020 564 56 0.0%
8/29/2020 831 61 0.0%
8/28/2020 1,289 111 0.0%
8/27/2020 2,070 227 0.0%
8/26/2020 2,463 365 0.0%
8/25/2020 1,660 298 0.0%
8/24/2020 1,736 284 0.0%
8/23/2020 481 71 0.0%
8/22/2020 447 44 0.0%
8/21/2020 990 132 0.0%
8/20/2020 2,011 236 0.0%
8/19/2020 1,055 146 0.0%
8/18/2020 1,434 139 0.0%
8/17/2020 1,746 235 0.0%
8/16/2020 849 55 0.0%
8/15/2020 915 95 0.0%
8/14/2020 1,722 231 0.0%
8/13/2020 895 92 0.0%
8/12/2020 934 148 0.0%
8/11/2020 1,219 200 0.0%
8/10/2020 1,427 157 0.0%
8/9/2020 803 89 0.0%
8/8/2020 714 62 0.0%
8/7/2020 1,171 178 0.0%
8/6/2020 671 112 0.0%
8/5/2020 1,104 191 0.0%

Blocks from web.de

No blocks during specified time frame

Bounces from web.de

Message Count
550 Requested action not taken: mailbox unavailable 574
554 web.de Nemesis ESMTP Service not available No SMTP service IP address is black listed. For explanation visit https://web.de/email/senderguidelines?ip=167.89.100.132&c=bl 120
554 web.de Nemesis ESMTP Service not available No SMTP service IP address is black listed. For explanation visit https://web.de/email/senderguidelines?ip=50.31.60.236&c=bl 93
554 web.de Nemesis ESMTP Service not available No SMTP service IP address is black listed. For explanation visit https://web.de/email/senderguidelines?ip=167.89.100.13&c=bl 77
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.66&c=sp 15
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.66&c=sp 14
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.194&c=sp 12
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.194&c=sp 9
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.196&c=sp 8
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.65&c=sp 8
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.128.66&c=sp 7
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.196&c=sp 7
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.65&c=sp 7
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.65&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.196&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.217.67&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.193&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.68&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=162.0.237.171&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.195&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.195&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.67&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.66&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.65&c=sp 6
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.160.196&c=sp 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.68&c=sp 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.128.65&c=sp 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.66&c=sp 5
554 Transaction failed Reject due to policy restrictions. For explanation visit https://web.de/email/senderguidelines?ip=149.72.128.25&c=hi 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.195&c=sp 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.194&c=sp 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.68&c=sp 5
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.195&c=sp 5
Email was deferred due to the following reason: 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.193&c=sp 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.68&c=sp 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.161.67&c=sp 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.67&c=sp 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.66&c=sp 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.193&c=sp 4
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.196&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.216.68&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.194&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.195&c=sp 3
554 web.de Nemesis ESMTP Service not available No SMTP service IP address is black listed. For explanation visit https://web.de/email/senderguidelines?ip=167.89.100.226&c=bl 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.194&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.195&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.67&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.67&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.194&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.66&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.193&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.160.193&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.68&c=sp 3
554 web.de Nemesis ESMTP Service not available No SMTP service Reject due to policy restrictions. For explanation visit https://postmaster.web.de/error-messages?ip=167.89.100.27&c=sp 3
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.217.68&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.216.67&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.196&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.65&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.214.196&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.194&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.68&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.214.195&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.66&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.128.67&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.214.193&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.216.66&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.217.66&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.66&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.68&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.65&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.67&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.67&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.161.68&c=sp 2
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.216.65&c=sp 2
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.128.67&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.181&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.161.66&c=sp 1
X-Postfix; delivery temporarily suspended: host mx-ha03.web.de refused to talk to me: Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=192.185.149.101&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.46&c=quot 1
550 Sender frequency limited. http://service.exmail.qq.com/cgi-bin/help?subtype=1&&id=20022&&no=1000723 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.177&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.172&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.67&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.53&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.160.195&c=quot 1
SMTP; mail action aborted: exceeded storage allocation 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.182&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.51&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.196&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.46&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.195&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.68&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.65&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.52&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.196&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.65&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.67&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.174&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.160.194&c=sp 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.196&c=sp 1
554 web.de Nemesis ESMTP Service not available No SMTP service IP address is black listed. For explanation visit https://web.de/email/senderguidelines?ip=50.31.63.190&c=bl 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.219.196&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.43&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.218.65&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.42&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.41&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.161.66&c=quot 1
X-Postfix; delivery temporarily suspended: host mx-ha02.web.de refused to talk to me: Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=192.185.49.60&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.175&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.194&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.174&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.214.193&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.216.46&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.66&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.161.65&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.214.177&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.216.49&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.215.171&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.193&c=sp 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.65&c=sp 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.65&c=sp 1
554 web.de Nemesis ESMTP Service not available No SMTP service IP address is black listed. For explanation visit https://web.de/email/senderguidelines?ip=167.89.100.167&c=bl 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.167.194&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.66&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.210.47&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.161.65&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.193&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.221.194&c=sp 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.50&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.166.195&c=quot 1
mail action aborted: exceeded storage allocation exceeded. 552 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.208.42&c=quot 1
Nemesis ESMTP Service not available 554-No SMTP service due to policy restrictions. 554 For explanation visit https://postmaster.web.de/error-messages?ip=209.85.222.193&c=sp 1

Methodology

Send and open statistics are updated daily. Bounces and blocks are updated in real-time. Every day, open statistics are updated for the last 14 days. Generally, you'll notice an increase of an open rate for a domain for a day over the course of 14 days, since not all open events occur the same day an email is sent. That means that open rate data is tied to the actual emails sent on a particular day.

Bounce and block codes are the codes as returned by the remote SMTP server after having been de-personalized. Meaning, unique identifiers present in SMTP codes are removed so that SMTP responses can be grouped for analysis. In certain cases, such as when the email is being relayed through an intermediary SMTP server, the remote SMTP server may not be the same as the MX record for the domain. SMTP codes are categorized as "bounces" vs "blocks" by internal human review. Bounces generally indicate an invalid email address. Blocks generally indicate a rejection of the email message but a valid email address.