Undefined function or variable 'parforstart'

Running a .m file on a new computer, I get the error message: Undefined function or variable 'parforstart'

I have no idea what's going on. There is little on this in Google. The only answer is this is because I didn't have Parallel Processing Toolbox on the new computer. But I don't have this toolbox in the old computer either! What's going on? Help Please!

[Sean de Wolski]

>> which -all parforstart

What is the line of code throwing the error and the FULL contents of the error message?