Posts Tagged ‘IMAP’

Another iPhone ‘LIST-STATUS’ issue [FIXED]

Posted on: February 15th, 2019 by

In the beginning of the week we got a list of reports from users of iPhone connected via IMAP. These users reported that they were unable to list their mail folders. You can read about this issue in a previous blog post on this blog.

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Another iPhone ‘LIST-STATUS’ issue..

Posted on: February 13th, 2019 by

A little more than a year ago, we found and worked around an issue that caused iPhone users to have problems with IMAP connections to Kolab Now. The issue made it problematic for such users to list and read their IMAP folders.

Back then we worked around the issue by suppressing the LIST-STATUS option for IMAP connections, which made everything work for a while.

This week we again started getting a number of reports about similar symptoms from iPhone users, and we of course investigated those reports as fast and appropriate as we always do.

We quickly found, that a change was made in January to fix an issue for  Outlook users, and that one part of that change was – you guessed it – to undo the suppression of LIST-STATUS. Hence, IMAP connecting iPhone users were getting right back into almost the same situation that they were in a year ago.

Where as we have found the root cause of the issue, we seem to be in a catch 22, where we can accommodate Outlook users or iPhone users connecting via IMAP. Of course we are working on a fix that can make it possible to accommodate both groups of users. Updates and news about the issue will be posted here in this blog.

If you need to read mail and list mailfolders on your iPhone before we have fixed the issue, there are at the moment two workarounds:

Should you have any questions or concerns in this context, then please contact Support.

The Kolab Now Team thank you up front for your patience.

Outlook and return options to LSUB

Posted on: January 9th, 2019 by

A while back, users started to experience issues with IMAP LIST Extension for Special-Use Mailboxes. This to a level where a decision was made to temporarily suspend supporting Special-Use at Kolab Now.

Lately we have found ways to get around the problems that were present back then, and over the change of the year we introduced an update that, among other great improvements, contained these solutions and re-enabled the Special-Use.

Unfortunately, meanwhile Microsoft has also updated Outlook, and their update has changed the return options that Outlook is using with the LSUB command on the IMAP server.

This has caused issues for some users, who connect Outlook to Kolab Now via IMAP. Those users are suddenly not able to see some of their folders and mails in Outlook. The folders are perfectly visible in the web client and in other IMAP clients like mobile clients, Mac Mail and Thunderbird.

While the RFC compliance issue (the LSUB command does not accept a client specifying RETURN options) certainly has been made visible by Microsoft changing the behavior of Outlook, inversely Kolab Now providing an update to the benefit of all other clients has suddenly shown the related Outlook behavior to be faulty.

The root cause of the issue can be narrowed down to the expectations from Cyrus IMAP while parsing the LSUB command. Besides filing an upstream ticket, Kolab Systems has engaged in this issue and is contributing a fix to the Cyrus IMAP code. This fix is now going through test and QA, and should be ready to be deployed to Kolab Now soon.

If you are one of the users, who has problems because you are connecting Outlook to Kolab Now via IMAP, then you can work around the issue by – either using another IMAP client – or by connecting your Outlook to Kolab Now via ActiveSync, until the fix for Cyrus IMAP is ready and deployed.

If you have any questions or concerns in this context, then please contact support@kolabnow.com.

iOS IMAP Connection Issues Resolved

Posted on: November 7th, 2017 by

In the last few days, I’ve spent hours and hours configuring accounts on my private iPhone 6 running iOS 11 in order to attempt to nail down where its connection issues originate.

I’m happy to be able to tell you I seem to have nailed it down, and there’s a quick fix for it, that we can apply on the server-side.

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Incident Report: Backend Down

Posted on: October 17th, 2017 by

Earlier this morning, at 04:38 UTC, one out of the twenty-two IMAP backends in production stopped serving its mail spool, showing Input/Output errors on its disk. Our Standard Operating Procedure is to examine log files, flush vm caches, stop the virtual machine, and start it back up again. This occurred at 05:48 UTC. The IMAP backend in question did not come back up cleanly.

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