Google says it could be an AOL file related to WinAmp, or a file related to Dell Datasafe Local, or possibly something else.   I'm guessing it's Datasafe Local trying to make backups, but as I don't have it, I can't tell you for sure.

Rather than guess,  do a search on your PC for toaster.exe and see what program folder it's listed under.   Once you know the program, it'll be easier to figure out if it can be disabled or fixed.

my problem is that my computer says that "it couldn't found toaster.exe."

what should i do ? will the effect my laptop performance, or will it cause my laptop to crash?

please refer this link, may be helpful to you..

nw360.blogspot.com/.../small-top-margin-on-windows-7-desktop.html