Software Update

Suddenly my Software Update will not open, I get a "quit unexpectedly" error. This also happens when I try to open the App Store and when I try to install new software with a dmg file I get the same error message.

I have tried deleting all files from the librarypreferences labeled: com.apple.SoftwareUpdate. Then I restart, yet it doesn't help. I ran disk permissions and repaired them as well still nothing helps.

Any other suggestions other than reinstalling the software? I have 10.6.8 installed.