# TLS Connection Error SendMail tls: first record does not look like a TLS handshake **URL:** \ **Category:** Troubleshooting\ **Created:** [May 14, 2019, 7:16am UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283 "2019-05-14T07:16:21Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![marutinandanpandya](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/marutinandanpandya/32/2889_2.png) [@marutinandanpandya](https://forum.mattermost.com/u/marutinandanpandya)\ **Post date:** [May 14, 2019, 7:16am UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/1 "2019-05-14T07:16:21Z")
I created an IAM User with SES access for SMTP in AWS. Even the test email fails with the following error. > {“level”:“error”,“ts”:1557817125.2576823,“caller”:“web/context.go:52”,“msg”:“Connection unsuccessful: SendMail: Failed to open TLS connection, tls: first record does not look like a TLS handshake”,“path”:“/api/v4/email/test”,“request\_id”:“XXXnpxm97ffhzp9cgixiXXXXX”,“ip\_addr”:“157.37.133.140”,“user\_id”:“”,“method”:“POST”,“err\_where”:“testEmail”,“http\_code”:500,“err\_details”:“”} Enabled SMTP Auth is set to true SMTP server: [email-smtp.us.east-1.amazonaws.com](http://email-smtp.us.east-1.amazonaws.com) SMTP port: 587 SMTP username: User access\_key SMTP Password: secret\_key Connection is TLS iam policy attached is > ``` > { > "Version": "2012-10-17", > "Statement": [ > { > "Sid": "VisualEditor0", > "Effect": "Allow", > "Action": [ > "ses:SendEmail", > "ses:SendRawEmail" > ], > "Resource": "*" > } > ] > } > > ``` Mattermost Versions Test: 5.10, 5.9.1 ---
**Author:** ![amy.blais](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/amy.blais/32/7481_2.png) [@amy.blais](https://forum.mattermost.com/u/amy.blais)\ **Post date:** [May 14, 2019, 3:33pm UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/2 "2019-05-14T15:33:41Z")
Hi @marutinandanpandya, Wondering if this previous thread might help: [[solved] TLS Connection Error SendMail Failed to Open TLS - on SES Amazon SMTP credentials in Config/Mattermost JSON](https://forum.mattermost.com/t/solved-tls-connection-error-sendmail-failed-to-open-tls-on-ses-amazon-smtp-credentials-in-config-mattermost-json/7104)? ---
**Author:** ![marutinandanpandya](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/marutinandanpandya/32/2889_2.png) [@marutinandanpandya](https://forum.mattermost.com/u/marutinandanpandya)\ **Post date:** [May 14, 2019, 3:59pm UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/3 "2019-05-14T15:59:45Z")
Nope. Already saw that. As the person mentioned he was testing with the wrong creds and fixing the creds solved the issue. Same is not the case here, I created the IAM User specifically with SES access and yet the issue. (Also tried sending emails with user having administrative access, yet the same issue) ---
**Author:** ![amy.blais](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/amy.blais/32/7481_2.png) [@amy.blais](https://forum.mattermost.com/u/amy.blais)\ **Post date:** [May 20, 2019, 2:49pm UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/4 "2019-05-20T14:49:56Z")
Hi @marutinandanpandya, can you try using port [456 or 2456](https://docs.aws.amazon.com/ses/latest/DeveloperGuide/smtp-connect.html)? ---
**Author:** ![djangofan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/djangofan/32/3650_2.png) [@djangofan](https://forum.mattermost.com/u/djangofan)\ **Post date:** [March 29, 2020, 2:18am UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/5 "2020-03-29T02:18:28Z")
I am having the exact same issue but there is not quite enough information on this thread to resolve me. I’m using AWS SES email service: [email-smtp.us-east-1.amazonaws.com](http://email-smtp.us-east-1.amazonaws.com). I get 1 of a few errors: 1. TLS 587: Connection unsuccessful: Connection unsuccessful: SendMail: Failed to open TLS connection, tls: first record does not look like a TLS handshake 2. TLS 465: Connection unsuccessful: Connection unsuccessful: SendMail: Error setting “From Address”, 501 Invalid MAIL FROM address provided 3. TLS 25: hangs, and nothing shows up in the log 4. STARTTLS 465: times out and then says Connection unsuccessful: Connection unsuccessful: SendMail: Failed to open TLS connection, EOF ---
**Author:** ![amy.blais](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/amy.blais/32/7481_2.png) [@amy.blais](https://forum.mattermost.com/u/amy.blais)\ **Post date:** [March 30, 2020, 12:31pm UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/6 "2020-03-30T12:31:12Z")
What are your SMTP settings set to? ---
**Author:** ![ahmaddanial](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/ahmaddanial/32/2938_2.png) [@ahmaddanial](https://forum.mattermost.com/u/ahmaddanial)\ **Post date:** [April 2, 2020, 6:22am UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/7 "2020-04-02T06:22:27Z")
Hi, @djangofan Let us troubleshoot this based on the information provided in the official [SMTP Email Setup](https://docs.mattermost.com/install/smtp-email-setup.html#amazon-ses): - Set **SMTP Username** to **[YOUR\_SMTP\_USERNAME]** - Set **SMTP Password** to **[YOUR\_SMTP\_PASSWORD]** - Set **SMTP Server** to **[email-smtp.us-east-1.amazonaws.com](http://email-smtp.us-east-1.amazonaws.com)** - Set **SMTP Port** to **465** - Set **Connection Security** to **TLS** With reference to the following error that you are getting: > [@djangofan](#): > > TLS 465: Connection unsuccessful: Connection unsuccessful: SendMail: Error setting “From Address”, 501 Invalid MAIL FROM address provided Let us take a look at your Mattermost email settings. Can you please run the following command on the terminal and provide the result with the sensitive information such as password redacted: ```auto cat /opt/mattermost/config/config.json | grep -A29 "EmailSettings" ``` Also, are you getting those errors you listed when you click on the **Test Connection** button based on the combination of SMTP Server Port and Connection Security? ---
**Author:** ![djangofan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/djangofan/32/3650_2.png) [@djangofan](https://forum.mattermost.com/u/djangofan)\ **Post date:** [June 20, 2020, 12:30am UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/8 "2020-06-20T00:30:23Z")
Thank you @ahmaddanial I finally figured out how to solve it. 1. My “Route 53” DNS record needed to be re-validated (via the SES settings) so that the corrrect DKIM entries (3 of them) were added to my DNS record. That , in combination with me using a AWS SES validated email was the first half of the trick. 2. Secondly, I needed to edit /opt/mattermost/config/config.json and add ReplyToAddress , FeedbackEmail, and FeedbackName. values (which my host DigitalOcean forgot to add for me) Thank you. Happy to have it working. ---
**Author:** ![ahmaddanial](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mattermost.com/ahmaddanial/32/2938_2.png) [@ahmaddanial](https://forum.mattermost.com/u/ahmaddanial)\ **Post date:** [June 21, 2020, 11:06pm UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/9 "2020-06-21T23:06:01Z")
Hi, @djangofan Excellent. Thank you for sharing the solution you performed on your end! ---
**Author:** ![mksa](https://avatars.discourse-cdn.com/v4/letter/m/50afbb/32.png) [@mksa](https://forum.mattermost.com/u/mksa)\ **Post date:** [May 27, 2024, 10:26am UTC](https://forum.mattermost.com/t/tls-connection-error-sendmail-tls-first-record-does-not-look-like-a-tls-handshake/7283/10 "2024-05-27T10:26:19Z")
I’m getting the same error message. Here are the settings: - SMTP Server: `smtp.mailersend.net` - SMTP Server Port: `587` - Enable SMTP Authentication: `true` - SMTP Server Username: `` - SMTP Server Password: `` - Connection Security: `TLS (Recommended)` - Skip Server Certificate Verification: `false` - Enable Security Alerts: `true` Log event: ```auto { "caller": "web/context.go:115", "err_where": "testEmail", "error": "testEmail: Connection unsuccessful: unable to connect to the SMTP server through TLS: tls: first record does not look like a TLS handshake", "http_code": 500, "ip_addr": "172.18.0.4", "level": "error", "method": "POST", "msg": "Connection unsuccessful: unable to connect to the SMTP server through TLS: tls: first record does not look like a TLS handshake", "path": "/api/v4/email/test", "request_id": "ziqfkwsfqp8ruxbbg9y6r3hb4e", "timestamp": "2024-05-27 10:03:37.666 Z", "user_id": "ezhhwcbtdiy13cyktd3qgy5xaa" } ``` My SMTP server is okay because I have other services using it and it works fine. I also checked the ReplyToAddress, FeedbackEmail and FeedbackName values which are set properly.