You have specified semicontinuous bounds for the specified variable using the @SEMIC function.  The variable was determined to be fixed to a particular value that violates its semicontinuous property.  For example, if X were specified to be semicontinuous using the statement @SEMIC( 5, X, 100), then X must be either 0 or lie within the range [5,100].  If the model generator determines that X is fixed at some value other than this, you will receive this error message.  The most likely cause of this error is incorrect semicontinuous bounds, i.e., in this example, the bounds of 5 and 100