EWS Error Code: ErrorMimeContentConversionFailed
Posted by on 14 May 2019 12:29

Problem: While archiving email from a Microsoft Exchange server an EWS error code ErrorMimeContentConversionFailed occurs.

Solution: This kind of Exchange internal server error is caused by an internal Exchange function that is not able to convert a message from Exchange's internal MAPI format into the RFC822 compliant MIME format which is also used by MailStore Server. In nearly all cases the original MIME message received by the Exchange server already contained invalid data, such as an appointment request confirmation without references to the original appointment. Therefore it is usually safe to delete those emails.


Due to that error the archiving profile itself terminates with a non-successful status code. This behavior can be changed since MailStore Server 8 by modifying the global property public.arcclient.skipMimeContentConversionFailed by executing the following command in MailStore's Management Shell:

store-setprop --name="public.arcclient.skipMimeContentConversionFailed" --value="true"

Please note: Independent of this global property, MailStore Server is neither able to archive messages where the above error occurred nor delete them from the Exchange server.

Article-ID: KB20130215-1-EN (Deutsche Version)

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