Blacklisting Bug: New Spam Complaint...From a Blacklisted Sub?



Today (26/02/2016) i've got a spam complaint....

....from a user that was blacklisted on 11/4/2015!

Take a look (ignore my typo on the blacklist date and see the date that shows MailWizz):


When i've checked at the message that he received (the one that triggered this new spam
complaint)...i've found that he got the broadcast that i've sent today.

This is serious.

Running v1.3.5.9
// Don't Know Which Could be The Cause, But I'll Try To Provide All The Information That I Can Just To Help //

Update: I went to my list and the susbcriber appears as "Confirmed".

But he is on the blacklist list.

I can't remember if this subscriber was blacklisted
.....before i've imported him to this list (i'll call it "xyz" list - to which i've sent
the campaign) or not.

In both ways...

a) if the user was already blacklisted at the moment i've added him
to the "xyz" list... he shouldn't have been added (or added to that list
as "Blacklisted").

b) if i've added the email to the blacklist after i've imported
it to my "xyz" list...he/she should be blacklisted from all
the lists.

I guess it works this way right?

If none of these points are failing....then here's another
thing that may help (or not)....

.....In this case, what i've found for this email address
was not all in lowercase (example: the address was
something like instead of

Does the system take everything to lowercase when...

- a subscriber is added
- a subscriber is blacklisted


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Update 2: When i went to edit the subscriber i've found (after clicking the "Edit button") ....

.....that his email was added as

....while in the blacklist....he appears as

Under MySQL...


Could it be the reason of this problem (don't know if it is or not - just trying to help)?

If so, in the fix please consider all the possible areas to lowercase the addresses at the entry point...

- When a user is added (or updated from a list) ....Manually, Via API, Import etc.
- When a user is blacklisted (or updated from the blacklist)....Manually, Imported, etc.
- When you use a batch tool (example: mass unsubscribe list).

And don't know if i'm missing something.

In addition to this (and if the cause of the problem was this of course), a fix would
be required to update our existing lists (a mass update - maybe after installing
a new update - to lowercase all past subscribers).


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@Diego - There was an issue with the email blacklisting in version, which fixed, so you might want to update your app to latest version and see if that fixes it.
Thanks Twisted,

I've followed almost all the bug reports for the previous versions (and updated with some manual patches),
but i'll be updating now to this version.

Can you confirm that this specific issue is fixed in the latest update?

Best Regards,

@Diego - While i am not 100% sure, it should be as there were some cases where blacklisting didn't work properly.If it doesn't, then i can look into it since you'll be using latest version ;)
Thanks Twisted,

Just in case, i've mass updated all the addresses to lowercase but
(quick question) is blacklisting case sensitive (the email addresses)?