Compiled is an option for various numerical and plotting functions which specifies
whether the expressions they work with should automatically be compiled. It may
be that the functions you are using have this option. Look in the Help Browser for
information on your functions or evaluated Options[YourFunctionName]. (Of course,
this is for Mathematica functions). The Option can be turned off by using
Compiled->False as part of the function's options.
Turning off Compiled will likely remove the errors but may or may not help the
A small example that shows what you are evaluating could be helpful.