Yesterday I have similar issue with one of my customer,
ePO other two services were running but Event parser was not starting. I did following:
open ePO authentication page--> I found windows admin credentials to connect with DB, I changed it to SA and apply settings. Restart all epo services including db and issue resolved.
How your SQL installed, Mixed mode or only with SA credentials ?
Your case is seems so complicated to discuss here. I am agree with hem to open the case.
2014-11-28 01:00:08,888 ERROR [mfs:pool-1-thread-8] services.DownloadService - SQL Exception trying to update products strings.
java.sql.SQLException: Violation of PRIMARY KEY constraint 'PK_EPOSoftwareCatalogStrings'. Cannot insert duplicate key in object 'dbo.EPOSoftwareCatalogStrings'.
Please check your time synchronization too because it is not right if it is new orion log and also there is other problem about insert duplicate key which is strange.
Do you have installed the purchased ePO with license or it is trial?
BTW I think opening the case is the best way of solution find.
I have faced the same problem but in my case my EPO application server password expired which i used to get login to the server.
See first thing as suggested by most of the people is to check sa login in your db,Because when we are not able to login most of the time event parser error comes.
Test database connectivity from EPO by http://localhost:8443/core/config.Select sa & verify sa password by test connection
Can you attach the screenshot of EPO GUI.