Visual Basic Concepts
Turns off error checking to insure that numeric values assigned to integer variables are within the correct range for the data types.
By default in Visual Basic, a check is made on every calculation to a variable with an integer-style data type (Byte, Integer, Long, and Currency) to be sure that the resulting value is within range of that data type. If the value is of the wrong magnitude, an error will occur. Selecting this option will turn off this error checking, which can speed up integer calculations. If data type capacities are overflowed, however, no error will be returned and incorrect results may occur.