OVH is blocking MailWizz specifically

I have been using MailWizz on OVH servers for about a year.

2 weeks ago, Port 25 was blocked on all my IPs with OVH. After some investigation, they said their new anti-spam appliance is blocking all outgoing emails sent with mailwizz. Their support said that customers using mailwizz usually sends a lot of spam and outgoing emails using mailwizz will result in port 25 getting blocked.

I looked at the outgoing emails and "MailWizz" is not present anywhere in the emails,

How are they detecting that the email is being sent by MailWizz and how do I make it say something else and not be detected as a 'Mailwizz' email?
 
I'll try it.

Perhaps that could be made into a back end setting, which would make upgrades easier.

or use X-"Domain Name" as the default email.custom.header.prefix
 
I got this reply from them:

Hello,

I have received a response from Vade-Retro on this issue. They are saying that MailWizz is blocked due to the detection of sent e-mails using practices used by spammers: False Answers (Such as marketing campaigns using mail objects starting with <<RE : >>), multi-domains and snowshoe. We have also received commercial e-mails on non opt-in. We can't allow MailWizz to be enabled.

We thank you again for choosing OVH,

Simon​
 
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This is strange. Why would they block the application. They can block spammers who abuse their network but why blame the software ? It does not make sense.
 
It is probably easier for them to block the software in general than to hunt down every little 'hero' that is using cheap ovh vps spmming the hell out of them...
...if the sw had only safe double opt-in mode, then it would be a different story...however, this is not feasible, as there are many legitimate single opt-in or just import-for-transactional-email purposes...
...and so mwz goes the way other mailers have gone, with standard headers detected and mail sorted to the spam heap, even the good ones...
...which leaves only the option to change headers and use spf, dkim and dmarc, and consistent from/bounce/replyto/returnpath, which spmmers usually avoid.
;)
 
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I have the same problem here, but the OVH said I was blocked due to the message content classified as spam.
 
Well, truth be told, OVH has serious issues with spammers using their systems...
Anyway, what i can do related to MWZ, is to generate the header prefixes automatically at install time...from next version.
 
It might be better if this was setup per customer-- it can be part of the customer settings.
Each customer with have their unique email.custom.header.prefix -- One customer getting blocked will not result in other users getting blocked.
 
It might be better if this was setup per customer-- it can be part of the customer settings.
Each customer with have their unique email.custom.header.prefix -- One customer getting blocked will not result in other users getting blocked.
this seems like the best solution for this issue, waddayathink @twisted1919 ?
 
I hardly doubt OVH is blocking the actual application. We still have multiple servers that run mailwizz that are not blocked at all.
However, we have had this issue twice now where Port 25 has been blocked on a server.

Vade-Retro saves patterns. It will save the header and the IP address once they detect spam. This can happen even if you sent legit email. We do not send spam but have been blocked in the past and is quite a headache to be un-blocked again on Vade-Retro's side.

The reason I think they do not block the application headers is due to the following. One of our servers was blocked and we then routed all mail from that server to another OVH server that used different IP's. The mails were detected as spam on the old server, but once routed to the other server they all got delivered. This clearly shows that the header alone was not the issue.

We have since started moving to a new network and are leaving OVH behind. Their support is slow, despite us having close to 20 dedicated servers. Another problem is that a lot of server admins world wide block entire OVH IP ranges by default. OVH back in the day was used by a lot of spammers.
 
hi .
any update about this mailwizz / ovh blocks ?
i was thinking to get a dedicated from ovh (and install mailwizz) and then delivery servers on others datacenters

tks
 
hi .
any update about this mailwizz / ovh blocks ?
i was thinking to get a dedicated from ovh (and install mailwizz) and then delivery servers on others datacenters

tks
Hey :) In last few months only I've installed multiple MailWizz for customers who are using OVH VPS & some Dedicated Servers they have never faced such situation ;) They're using Amazon SES, SparkPost, PMTA, Postal, etc.

As per my experience I feel it's purely related to usage of OVH VPS & IPs, if you're sending good emails they don't bother you :D MailWizz is not a problem for them at all.

If somebody SPAM and using any hosting company/datacenter they will face blocks, etc. because that type of emails directly effect hosting company/datacenter's network reputation.

Hope it helps!
 
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Hey :) In last few months only I've installed multiple MailWizz for customers who are using OVH VPS & some Dedicated Servers they have never faced such situation ;) They're using Amazon SES, SparkPost, PMTA, Postal, etc.

As per my experience I feel it's purely related to usage of OVH VPS & IPs, if you're sending good emails they don't bother you :D MailWizz is not a problem for them at all.

Hope it helps!
Yes, that is correct, no problems with OVH, as long as content (expected) and confirmations (requested) are OK ;)
 
I also confirm that OVH & Mailwizz works for me currently. @Osjtya made my settings thanks to him.
I didn't send emails in very bulk numbers yet. Although, emails were sent anyways. So no app block in this case. It would be ridiculous to block the app anyways if the client is not a spammer.
In my personal opinion, Somehow @twisted1919 should better consider some protective coding against spammers to preserve MailWizz 's future reputation.
 
Somehow @twisted1919 should better consider some protective coding against spammers to preserve MailWizz 's future reputation.

That's impossible to do, how is MW supposed to define what a spammer is, someone sending millions of emails everyday such as myself doesn't make me a spammer.

Something like that is not needed and will cause more problems/complaints than good.
 
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