Issue Your IMAP client does not appear to correctly implement Unicode messages, see https://tools.ietf.org

[Jose Isla]

Hi,
Yesterday we updated Plesk Obsidian 12.8.20 and this morning our clients report us an error when sending messages from IMAP server. It returns an error message:
The IMAP server wants to alert you to the following: Your IMAP client does not appear to correctly implement Unicode messages, see RFC 6855 - IMAP Support for UTF-8
Folders with special characters have been renamed incorrectly too.
How can we solve the problem?
Our clients have not changed their mail client: Outlook and before with the previous version of Plesk Onyx this did not happen to us.
Thanks !

 

[Jose Isla]

any ideas ?

 

[Stefan Müller]

Hey there,

got some customers who experience a similar issue.

They are reporting that since the update to obsidian they're receiving the following message:

Your IMAP client does not appear to correctly implement Unicode messages, see RFC 6855 - IMAP Support for UTF-8

They are using Outlook 2010, 2013 & Office365.

In Addition the the "Umlaute (Ä, Ö, Ü) are displayed as hieroglyphics.

Would be great to get some info how to fix that issues.

Thanks in advance,

Stefan

 

[Jose Isla]

It's frustrating, we have been like this since the weekend and without any solution. Help!

 

[sebgonzes]

You use dovecot or courrier?

 

[Jose Isla]

Courier IMAP

 

[sebgonzes]

It seem dovecot haven't this problem (I have update for now more than 40 servers and not have this issue with dovecot), sometime is an solution for you.
In anycase, review this :

Your IMAP client does not appear to correctly implement Unicode messages, see https://tools.ietf.org/html/rfc6855.html

=>
UTF8=ACCEPT in IMAP_CAPABILITY

 

[Jose Isla]

The strangest of all is that this did not happen before with Plesk Onyx ...

already change: UTF8 = ACCEPT in IMAP_CAPABILITY
in the mail clients without positive result.

So do you recommend upgrading to Dovecot?

Thank you so much !!

 

[sebgonzes]

The strangest of all is that this did not happen before with Plesk Onyx ...

So do you recommend upgrading to Dovecot?

Thank you so much !!

Well I just say that our clients haven't reportme this problem with dovecot (I don't use courier), but in your case, sometime before you had to try changing this parameter. With plesk update, sometime there is parameters that are overwriting (case of html email in horde) and sometime it's the case with the utf8 parameter in courier

 

[Jose Isla]

Many Thanks !!!
Any possibility to change the imap courier config manually on the server?

 

[sebgonzes]

You can review where are the config files :

Plesk for Linux services logs and configuration files

 

[Jose Isla]

Thanks !!

But it would be convenient for Plesk support to carry out an update to solve this problem ... from what we see there are more people with this problem.

I said thank you very much!

 

[Jose Isla]

Added "UTF8 = ACCEPT" in: etc/courier-imap/imapd

IMAP_CAPABILITY="IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA AUTH=CRAM-MD5 AUTH= CRAM-SHA1 AUTH=CRAM-SHA256 AUTH=PLAIN IDLE UTF8=ACCEPT"


and in :

IMAP_CAPABILITY_ORIG="IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA AUTH=CRAM-MD5 AUTH=CRAM-SHA1 AUTH=CRAM-SHA256 AUTH=PLAIN IDLE UTF8=ACCEPT"

Tomorrow we will know the results.

 

[sebgonzes]

Added "UTF8 = ACCEPT" in: etc/courier-imap/imapd

IMAP_CAPABILITY="IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA AUTH=CRAM-MD5 AUTH= CRAM-SHA1 AUTH=CRAM-SHA256 AUTH=PLAIN IDLE UTF8=ACCEPT"


and in :

IMAP_CAPABILITY_ORIG="IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA AUTH=CRAM-MD5 AUTH=CRAM-SHA1 AUTH=CRAM-SHA256 AUTH=PLAIN IDLE UTF8=ACCEPT"

Tomorrow we will know the results.

If it's works, mark this theme as resolved for other user that can have same issue.

 

[Jose Isla]

I'm waiting for that ... answer from my client ...
As soon as you communicate any news, I publish it here.

 

[Jose Isla]

Bad news, the client reports that today they have also received the alert. We are frustrated not to find the solution. Today we plan to update to GA Update 1 ..... we will see if it gives any results.

 

[sebgonzes]

Bad news, the client reports that today they have also received the alert. We are frustrated not to find the solution. Today we plan to update to GA Update 1 ..... we will see if it gives any results.

As it's an courier issue with, apparently, some specific message/client program, I understand that is not an clear bug of plesk and sometime not easy to solve by plesk team but courier team (the problem is report not only with plesk but with courier use in general), sometime you can try to change courier by dovecot as it seem work fine.

 

[Jose Isla]

The application used by our customers is the one they have always used: Outlook 2016.
And this problem did not occur in the previous version of Plesk.
When updating to Plesk Obsidian it has begun to fail.

The problem with upgrading to dovecot is: am I sure I won't have problems in this update? I have heard that IMAP folders with spaces when updating them to docevot also give problems ...

Your help is greatly appreciated and valued by us.

Many thanks !

 

[sebgonzes]

The application used by our customers is the one they have always used: Outlook 2016.
And this problem did not occur in the previous version of Plesk.
When updating to Plesk Obsidian it has begun to fail.

The problem with upgrading to dovecot is: am I sure I won't have problems in this update? I have heard that IMAP folders with spaces when updating them to docevot also give problems ...

Your help is greatly appreciated and valued by us.

Many thanks !

Plesk upgrade a lot of elements when updating ... but most of these elements are external and have is own development, as courier, dovecot, php, apache etc etc, plesk is only the panel that join all elements and offer an GUI to manage them easily and, almost is what I understand, have no direct responsability of an specific bugs between one of these elements and one client program as outlook from microsoft.
Obviously, I am sure that plesk team will review and try to give you an solution, but it's probably not an plesk bug/issue but an courier bug/issue or an outlook bug/issue in this case.

> The problem with upgrading to dovecot is: am I sure I won't have problems in this update? I have heard that IMAP folders with spaces when updating them to docevot also give problems ...

Well, I can't confirm you that you will not have problem, I know our server system, not your system, I only can confirm you that we have not issue actually with plesk obsidian and his dovecot version and imap/pop clients. In this case, better wait the confirmation of Igor.

Have you try to put an ticket?

 

[Jose Isla]

Thanks for your answer.

Yes, my hosting provider on my behalf has put a ticket and we are waiting for an answer.

We will wait for Plesk's support response and then decide whether to upgrade to Dovecot or not.

Thank you !