i can't find the sourcelist in cornerstone anymore -

i can't find source list in cornerstone anymore. have tried view>show source list, still can't find source list. , have tried reinstalling software, still doesn't work.

1. kill cornerstone process
2. delete config file users —> library —> preferences, there com.zennaware.cornerstone.plist file（cornerstone ui config file） delete file
3. restart machine