I was having the same issue a couple of months ago and I fixed it by enabling SRS support for my server.
Since I have spf enabled to improve deliverability, when an email gets received from gmail.com for example and your server tries to forward it to another gmail or a hotmail account or any other external domain... the domain arrives to the new destination as user1@gmail.com but since it goes out from your server which is not authorized to send using a gmail address... then the receiving end will most likely discard the message without telling you everything because it will consider it as spam or forfeited email.
With SRS enabled the same email will get forwarded with something like this: gmail.com+user1@yourserver.com
but the final user will not see that email unless they click on the "show source button on their email"... The email will be accepted by the final destination host because it appears to be sent from your domain where Sentora is installed, not a gmail yahoo, or any other domain.
This tutorial helped me fix it... I skipped the dkim part because I had already implemented it.
http://seasonofcode.com/posts/setting-up...stfix.html
Regards,
Heberth
Since I have spf enabled to improve deliverability, when an email gets received from gmail.com for example and your server tries to forward it to another gmail or a hotmail account or any other external domain... the domain arrives to the new destination as user1@gmail.com but since it goes out from your server which is not authorized to send using a gmail address... then the receiving end will most likely discard the message without telling you everything because it will consider it as spam or forfeited email.
With SRS enabled the same email will get forwarded with something like this: gmail.com+user1@yourserver.com
but the final user will not see that email unless they click on the "show source button on their email"... The email will be accepted by the final destination host because it appears to be sent from your domain where Sentora is installed, not a gmail yahoo, or any other domain.
This tutorial helped me fix it... I skipped the dkim part because I had already implemented it.
http://seasonofcode.com/posts/setting-up...stfix.html
Regards,
Heberth