When a call to a procedure or function in your delphi program returns fewer parameters than those indicated in the procedure or function declaration, this error message appears.
Calls to standard procedures or functions can also cause this.
program Produce; var X: Real; begin Val('3.141592', X); (*<-- Error message here*) end.
The procedure Val provides one more parameter in which to return an error code. That parameter was not included in the example.
program Solve; var X: Real; Code: Integer; begin Val('3.141592', X, Code); end.
Typically, you will compare the call to the declaration of the procedure called or the help, and you will discover that you have forgotten to specify an argument.