ECUnited,

Many times when an app was working and there was no change to it and it stops working, this could mean one of two things.

1) Database corrupted
2) User installed something which overwrote the database components with different versions.

You can correct both:

1) Use the databases repair programs on the database
2) Reinstall the database componebts.

You can use the Automatic OS Updater to reinstall the correct database components.