Users see one or more of their Calendar items recurringly showing and disappearing on their phones. The error seen in the Kerio Connect logs is:
Item ID "7:9992<!ExceptionDate!>20010101T000000Z" is in incompatible format.
[User: email@example.com, Device: (ER35654HJUHGVC3875)]
- This issue commonly occurs due to the corruption of the Kerio Connect's Calendar Folder of that user.
- Kerio Connect files could become corrupted or damaged during unexpected service crashes or server outages. The internal files might also be occupied by other applications and/or built-in OS services.
- Kerio Connect repairs these corrupted files automatically (since version 7.3.0) by re-indexing them. In case the automatic re-indexing is failing (due to which the errors are not resolved), you will need to do the indexing manually using the steps outlined in this article.
- Each Kerio Connect's user folder (INBOX, Calendar, Sent Items, etc.) contains its own index.fld file. One of the most common causes of inconsistencies/corruption in the index.fld file is a local anti-virus software that has not been configured to exclude the scanning of the mail server and the store directories. We strongly recommend using the built-in Bitdefender antivirus or one of the supported antivirus plugins included with Kerio Connect to scan messages for viruses.
- So, before proceeding further with the solution, exclude the Kerio Connect folders from any Antivirus scanning, since this can also cause data corruption issues. Find complete details in Antivirus Exclusions for Kerio Connect.
To implement the below steps, access to the Kerio Connect Administration interface will be required:
- Stop the Kerio Connect service (Windows, Linux/macOS)
Navigate to the Kerio store folder.
Access the user's Calendar via the following path (defaults):
- Rename the
- Start the Kerio Connect service (Windows, Linux/macOS)
- The user who was seeing the issue should access their Calendar now. Kerio Connect will rebuild the index file at that point. If it is a large folder, there might be a slight delay in the rebuilding process. The calendar items will be stable and no longer disappear on the user's phones.
- Log in to the Kerio Connect web administration interface, and check the error log. Errors related to incompatible format will no longer be seen.