Since applying Update Rollup 10 one of my customers are seeing Generic SQL Error messages with Quick Find. However, this is only on Lead; Account, Contact and other entities are fine.
It appears others are having this problem (see this post in German and this thread on the forums)
Quick Find has changed in UR10 and if you get errors with Quick Find then first check if you have any address fields in the list of Find Fields and remove them or you can use the OrgDB Settings Tool and set EnableQuickFindOptimization to zero which will set Quick Find behaviour back to pre-UR10 way of working.
If you want to find out more options check out the performance white paper.
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