The message indicates that the CPLEX presolve procedures has declared a model infeasible before the selected optimization algorithm begins. This early declaration saves considerable execution time in most cases. The log file will give you more information:
... Primal unbounded due to dual bounds, variable 'GFACAP(d2005.2020)'. Presolve time = 7.92 sec. Presolve found the problem infeasible or unbounded. Rerunning with presolve turned off. ...
scaind 1) or a manual scaling (Chapter 17.3 of the GAMS User's Guide) could improve tolerance issues. You may also try to solve the model with another LP solver.
GFACAP(d2005.2020). You may have to increase the default level for limrow (default is 3) to see the complete equation listing in the GAMS listing file.
Primal unbounded …). A more systematic approach is to set the GAMS/CPLEX option
Reduce(Default 3) to 2 which will only detect unboundedness in the presolve, while a setting of 1 will only detect infeasibility. These settings of the
Reduceparameter are intended for diagnostic use only.