Horde can't email Hotmail, but it can email Gmail? 550 OU-002

[LordLiverpool]

Hello Parallels

Technical Details

I have a VPS from 123-Reg.co.uk
It's running Parallels Plesk:

OS: Linux 2.6.32-71.el6.x86_64
Panel version: 10.4.4 Update #52,
last updated at July 3, 2013 03:20 AM

I created a website for a customer.
He asked for email accounts on his domain.
So I created some accounts via the Parallels Panel

Panel > Subscriptions > Open in Control Panel > Mail > Create E-mail Address

lets pretend I created an account called [email protected]

All OK

Problem

Then I sent an email to my xxx@hotmail.com account I got the following error message back:

<xxx@hotmail.com>: host mx3.hotmail.com[xx.xx.xx.xx] said: 550
OU-002 (COL0-MC4-F47) Unfortunately, messages from yy.yy.yy.yy weren't
sent. Please contact your Internet service provider since part of their
network is on our block list. You can also refer your provider to
http://mail.live.com/mail/troubleshooting.aspx#errors. (in reply to MAIL
FROM command)

I got the same error message when I sent an email to my xxx@yahoo.com account.
But I DON'T get the error message when I send an email to my xxx@gmail.com (no problem)

Now here is the strange thing, if I send an email into my [email protected] from any email account it arrives at the Horde email account no problem.

I can reply to ANY email that arrives at my [email protected] without any problems.

There just seems to be a problem when I try to email someone who I haven't emailed before.

Questions

So I have 2 questions really:

Why do I get a 550 OU-002 error message when emailing someone?
Why don't I get an error message when emailing a Gmail account?

If I have posted my question in the wrong place, I apologise.
If no one can help, can someone please point me in the right direction.

Thanks in advance for your help.

 

[LordLiverpool]

ok so after some further investigation I have discovered the following

My VPS provider said that my IP address could be on an email blacklist for spamming

That made me think of three possible situations:

1. I haven't done any spamming!
2. Someone else sharing my VPS and therefore my IP address could be spamming (should I upgrade to a dedicated server with its own IP address?)
3. My IP address was at some point in the past used for sending spam (very likely) and therefore its now on a blacklist.

So then I realised that Webmail is just an application sitting on top of Plesk and maybe I was asking the right question but to the wrong people???

I contacted Horde and learned:

1. They don't answer their twitter account.
2. They don't have a forum where you can post questions.
3. If you want help you subscribe to mailing lists or IRC, How 1990's!! Get with the times guys!!!

I looked at my VPS and I have a choice of

AtMail (1.05) - development discontinued
or
WebMail (4.3.9) - only 5.0 and above supported

If I was to upgrade Plesk from 10.4.4 to 11 would I get any more options/settings to be able to send an email successfully? or am I barking up the wrong tree?

Is this simply a blacklist issue?

Anyone got any thoughts? suggestions? help? a URL to a horde forum??

Cheers

 

[LordLiverpool]

Will any of these settings fix my email?



Its frustrating get this message all the time:

<[email protected]>: host mx3.hotmail.com[xx.xx.xx.xx] said: 550
OU-002 (COL0-MC4-F47) Unfortunately, messages from yy.yy.yy.yy weren't
sent. Please contact your Internet service provider since part of their
network is on our block list. You can also refer your provider to
http://mail.live.com/mail/troubleshooting.aspx#errors. (in reply to MAIL
FROM command)

 

[Faris Raouf]

I think your VPS provider could do with being a bit more helpful. These are the kinds of question that is best directed to them, as it isn't really directly Plesk-related.

I will first of all offer you a crumb of hope. The error message you quote says "part of their network is on our block list". This could mean that your VPS's IP (which you would not normally share with anyone else unless it is a really strange VPS configured in a very unusual way) could be being blocked due the actions of other customers of your VPS provider and not you. Basically, some blocklists (including Microsoft's) will block a range of IPs even if spam only comes from one IP within that range. Your VPS provider should contact Microsoft to figure this one out if they don't already know the answer).

The type of webmail you have has nothing to do with anything -- yes, totally wrong tree

In general, the settings in the Plesk email settings page have nothing to do with anything either. However, you may like to investigate the Domain Keys section (please read the Plesk admin manual for more about this) as many big companies like to see email signed with domainkeys. Having SPF records are also useful, maybe more useful. Note that SPF section on that email settings page is only to do with incoming email, not outgoing. Use Google to research SPF records for more information on how to implement them in the DNS records. Implementing DomainKeys and SPF records will not cause you to be unblocked by Microsoft. Your ISP needs to do this, if they can, as mentioned previously, but it will help with deliverability in some cases.

Unfortunately your VPS could easily have been used to spend spam. One or more sites on your VPS could have been compromised by the bad guys, or they could have guessed an email username/password combination and could be sending spam by the million right now. Check the mail queue tab to make sure there are no significant numbers of messages. If there aren't then you should be fine and all is well. But never use easy to guess passwords or dictionary words for passwords.

The previous user of the IP being used by your VPS could have been used to send spam, yes. Most blacklists will expire an IP that has been "clean" after a while, but some do not. Microsoft is one such. Your VPS provider needs to contact them to deal with this as I mentioned previously -- there is no point in you attempting to do so. They are very difficult to deal with indeed and you are unlikely to get anywhere without expert knowledge.

All of this is only the tip of the iceberg. You really need your VPS provider to help you here if they are willing.

As to switching to a dedicated server - well, the only way that would help you would be that they are more expensive, and typically the people who rent them will take care of them better and their IPs are less likely to be blocked. Slightly less, anyway.

 

[LordLiverpool]

Hi Faris,

Once again, thank you very much for all your help, I am very grateful.

Ok the main thrust of your response seems to be get back in touch with my VPS provider.
To be honest I don’t hold out much hope. I think they are just interested in profits and not support. Although I will of course pursue them relentlessly!

With regard to you other points I will repeat them back to you, so you know if I have understood you correctly:

1.) Ask VPS provider to check with Microsoft if a block of IP addresses is on a blacklist.
2.) The email application “Webmail” makes no difference.
3.) The setting in Plesk’s email settings page makes no difference.
4.) My passwords all score “very strong” on the Plesk indicator bar.
5.) I checked the mail queue, zero activity right now. I will check periodically. (see screen shot)
6.) If my IP address was blacklisted it should eventually drop off the blacklist.
7.) Switching to a dedicated server will just cost more money and not fix the problem.

Ok so I have three things to do next:

1.) Contact my VPS provider.
2.) Investigate Domain keys. (see Plesk manual)
3.) Investigate SPF records. (on that Plesk page it’s incoming only) and implement via my DNS

Here is a screen shot of my mail queue, so you know if I am looking in the right place.



Thanks very much Faris, you are a good person.

Cheers

 

[LordLiverpool]

Hi

Just to round this post off

Three things needed to happen to fix this issue:

1. my VPS provider created reverse DNS records.
2. I created SPF records for each domain.
3. I upgraded my email to Qmail.

After that all domains could send/receive emails

I hope this final post helps someone at some point in the future

Cheers