Comment 89 for bug 966247

Every time i logged on, kactivitimanager crashed sooner or later. Also Kmail crashes very often while using.
Virtuoso-t process consumes about 30% of my Quad-Core CPU load, although strigi doesn't index anything.
I also noticed a strong delay when logging in, until kmix, klipper and strigi symbols came up.

Some of my interestingly findings:
After logging into the desktop, before the activitymangerd crashes, the akonadi test results was fine, after the crash the following fault was in:
Nepomuk search service not registered at D-Bus.
If the crash happens very early after log in, the kmix, klipper and strigi symbols doesn't came up at all sometimes.

I tried every forum and bug report hints i could find, nothing works until...
I deleted the following directory ~/.kde4/share/apps/nepomuk (while not logged into kde of course).

Logging in is pretty fast now, kmail much more responsive than before, and kactivitymanagerd doesn't crash once since this.
Akonadi's error log is clean now and hopefully stays so.

So that's the solution for me and also for another guy who takes this advice, I gave to him in the gentoo forum. Eventually this is the reason for some other bugs like the virtuoso CPU consumption Bug 293641 and one reason for kmail crashes too - hopefully.

So give it a try, but beware of the fact that if you've done some tagging of indexed files, this would be lost in this case and a new re-indexing of your hard drive is necessary!
Do a backup before or something else to save your work, if its important for you.

Much success, Andy.