How to reindex akonadi database without having to reconfigure?

[ianseeks]

Hi

I'm having the "Retrieving folder..." error message on every folder that 
contains an unread item. Akonadi fsck/vacuum/top/start no longer fixes the 
problem.
I have in the past followed the how to fix akonadi when there was a failed 
migration and that did all the work but it seemed like a hammer to crack a nut 
as you have to reconfigure kmail etc.

Is there a way to just delete the data and any related indexes to force a 
reindexing process?

I'm running out of ideas hence i hope this idea may help

Regards

Ian
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opensuse:tumbleweed:20170131
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