Corrupted index cache after migrating from maildir to mdbox

Tim tim at
Fri Nov 21 13:04:19 UTC 2014

On 21.11.2014 11:58, Toni Mattila wrote:
> Hi,
> I think your issue is due to your corrupted maildir sizes in filenames
> so you got corrupted index that way to your mdbox. That is not
> something you can easily fix afterwords other than fixing the maildir
> first and then migrate to mdbox.
well, I don't have the maildir files anymore or they are way out of
date. I can try to mirror the directory structure with doveadm to create
another mdbox instance. maybe this will it also fix.

> Best Regards,
> Toni
> On 21.11.2014 11:59, Tim wrote:
>> Hi Timo,
>> sorry for the late reply, missed this mail.
>> On 15.10.2014 05:05, Timo Sirainen wrote:
>>> On 27 Sep 2014, at 17:48, Tim <tim at> wrote:
>>>> unfortunately I'm getting the following two kinds of error messages
>>>> for
>>>> all mail boxes in my mail.log:
>>>> Error: Corrupted index cache file
>>>> /home/vmail/%domain/%user/mdbox/mailboxes/%maildir/dbox-Mails/dovecot.index.cache:
>>>> Broken virtual size for mail UID 2564
>>>> and:
>>>> Error: read(/home/vmail/%domain/%user/mdbox/storage/m.108
>>>> ): FETCH BODY[] for mailbox %maildir UID 2564 got too little data:
>>>> 2417
>>>> vs 6319
>>> If that happens to all the mails, something went wrong. Did you
>>> maybe use zlib plugin while writing the messages (compressed), but
>>> now you're trying to read the mails without zlib plugin?
>> the migration from maildir to mdbox is a few weeks in the past so I
>> don't remember correctly. IMHO I migrated from maildir with disabled
>> zlib to mdbox. with mdbox, zlib was active the hole time and it is still
>> active. Here is my doveconf -n output: .
>> Do you need anything else for debugging?
>>> The error messages may be somewhat confusing. The problem isn't
>>> dovecot.index.cache file, but that the message sizes in the m.*
>>> files don't match the contents. There's no easy way to fix those,
>>> because they should just about never be wrong.

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