.world files wont open wrong application linked,

[sallybear11]

now that i completely screwed up and somehow managed to change the way all .world files open, i have no way of discovering what the 

'UNKNOWN APPLICATION"  was originally, does anyone know?  cant open a dam thing, and its all my own doing.

cant open any saved files linked to the .world files in either sims 3 or create a world tool.   ????

im so pissed .................with myself.