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Issue Messages with Unicode unable to pick up via IMAP after upgrade

The issue is under developer's investigation as report PPS-7008.
Try to switch to Dovecot as a workaround.
 
Information from developers:

Root cause: new Courier-IMAP 5 implements rfc6855 and its developers opted to ALERT any IMAP client that attempts to fetch a mail message with national symbols (UTF-8) in headers, but didn't explicitly enable UTF-8 support. Outlook does exactly this.

How to fix: there is no fix available. Outlook doesn't seem to support rfc6855 at all. My recommendation so far is to do either of:
  1. Just deal with it (messages are annoying but the messages themselves are displayed correctly);
  2. Use another mail client, e.g. webmail.
Internal report PPPM-11248 was submitted.
 
Thanks for the info and the work IgorG !!

Total disappointment! ... but I suppose there is another solution that you don't indicate:

Migrate to Dovecot

True ?

Thanks !!!!
 
Hi Igor,

Information from developers:

Root cause: new Courier-IMAP 5 implements rfc6855 and its developers opted to ALERT any IMAP client that attempts to fetch a mail message with national symbols (UTF-8) in headers, but didn't explicitly enable UTF-8 support. Outlook does exactly this.

How to fix: there is no fix available. Outlook doesn't seem to support rfc6855 at all. My recommendation so far is to do either of:
  1. Just deal with it (messages are annoying but the messages themselves are displayed correctly);
  2. Use another mail client, e.g. webmail.
Internal report PPPM-11248 was submitted.

thank you for your message.
but that is not a pure outlook problem.

there are customers who use thunderbird or macmail and also have this message.

This only happens with isolated emails. For example, a customer receives an email a day from an email distributor and suddenly after the update, the message because of the unicode.

does PPPM-11248 mean that the plesk developers will solve the problem or is this something that only courier will solve with a new version?
 
A bit of background information - Courer IMAP has recently implemented RFC 6855, while other IMAP servers seem to be lagging behind. This has, among other things, revealed a number of issues in the client software.

It looks like they are considering adjusting alerts, but apart from that, they see the ball as being on the client side.

Some additional information:

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

Outlook 2016 with Courier-IMAP 5.0.8 append alert

Thunderbird (latest) POP3 UTF8 Cannot display Unicode content

Unicode alert feature
 
thanks ales for the info

this is of course great if the developer of a server software implements a rule without first checking exactly whether the clients fully implement this rule.
then we'll wait and see whether either the clients make corrections or courier changes.
 
We now have the same problem on my thunderbird. I download mail and I get lots of these warnings :(
I am switching to dovecot..wish me luck :)
 
Last edited:
I just switched to Dovecot because of this issue. The SSL certificate of the mail server is not copied across it seems. That and all downloaded mail is being re-downloaded by everyone..
I am working on these now.
 
Hi Igor, Ales,

Do you have more information from Courer IMAP since Nov. 14?
Has their position changed?
 
Hi all,

this is really annoying. We have the same issue here since a few days now and customers are getting really aggresive as Outlook is (at least in our country) the one and only standard. Anyone feedback how about the migration to Dovecot works?

Thx
 
Hi all,

this is really annoying. We have the same issue here since a few days now and customers are getting really aggresive as Outlook is (at least in our country) the one and only standard. Anyone feedback how about the migration to Dovecot works?

Thx
I am not sure, but suppose that only change it in upgrade plesk page is enough, someone of plesk team can confirm it? @IgorG ? Sometime is the best ways for now to not have the problem with your clients.
 
Hi all,

this is really annoying. We have the same issue here since a few days now and customers are getting really aggresive as Outlook is (at least in our country) the one and only standard. Anyone feedback how about the migration to Dovecot works?

Thx

Like tkalfaoglu, we have switch to Dovecot . It's going pretty well. The most important problem is that all email accounts resynchronize. So big traffic to anticipate and customers can see emails disappear before coming back ...
 
Like tkalfaoglu, we have switch to Dovecot . It's going pretty well. The most important problem is that all email accounts resynchronize. So big traffic to anticipate and customers can see emails disappear before coming back ...

Good information for every one that still have problem with courriers!
 
Hi there,

we have the same problem with a lot of mail addresses. Most of our customers are using Outlook. Is anybody here how could tell me if this issue will be fixed? And if then when?

For those who have switched from Courier to Dovecot via WebInterface have there been any problems despite re-sync?

Many thanks for your answer and kind regards!
 
when the fix is coming

Like IgorG said: the Warning-Message itself is right. So All the Companys providing the Email-Clients the Message pops up should fix this. Its their fault.
Ofc it would be nice if Plesk would have a setting where to bypass this check and just not send this warning but in the end you should not expect a fix from plesk.
 
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