Mail not delivered to gmail

1

Hi,
can someone please let me know the reason why this email was not delivered:

I am deeply sorry,
but I was not able to deliver your mail to the following addresses:

tbvtranslation@gmail.com : 5.7.26 This message does not have authentication information or fails to 5.7.26 pass authentication checks. To best protect our users from spam, the 5.7.26 message has been blocked. Please visit 5.7.26 https://support.google.com/mail/answer/81126#authentication for more 5.7.26 information. v9si6241896edd.297 - gsmtp

2

Hi,

you will have to give us some more info on your server / installation.
There are many, many reasons for a rejection like this, two obvious ones: No reverse DNS entry for your host and a missing / incorrect SPF record.

Cheers JK