When searching for events in the Event Policy UI, the MidTier Connector is not retrieving any events. However Alerts are being published from connectors. Since MTC doesn't show any events we are unable to create & deploy Event Policies on MTC. There are no event files in \SOI\resources\core\eventstore folder except 'temp' and 'archive' folders.
Solution:
When there are no files in the event store and if you see below exception in the \SOI\log\ssa.log, the problem could be with the available disk space.
[Storer timer thread] plugin.AbstractPlugin - Storer.Archive:Exception:Event store cannot write on system because it passed the free disk space threshold set by DESTORE_FREE_DISK_SPACE configuration option.
Free disk space: 20
Space available: 7
SOI 3.2 has additional "ESTORE" parameters in \jsw\conf\SAM-IntegrationServices.conf to configure the event store. ESTORE_FREE_DISK_SPACE sets a minimum required percentage of free disk space(Default is 20%). If the drive is more than 80% full, that could be the problem. Please refer the 'SOI Event and Alert Management Best Practices Guide' for more details. So, make sure the drive has sufficient space or adjust the "ESTORE" parameter values in the above mentioned config file.