Originally posted by: sultan0416052091

Hi , I am trying to solve 80bau3b benchmark of linear programming problem by cplex optimizers . Before passing the problems to cplex, I have done some preprocessing . Afer that when I pass the problem to cplex I have got the following error : 

Default variable names x1, x2 ... being created.
Default row names c1, c2 ... being created.
CPXPARAM_Read_APIEncoding                        "UTF8"
Infeasibility row 'c1':  0 <= -7634.
Presolve time = 0.02 sec. (0.28 ticks)
LP problem could not be solved

The model is attached with this thread. Please help me . I am in a lot of problems .  

Your model is blatantly infeasible and CPLEX tells you so in the output. You have
 c11:   x11  = -7752.24

but variable x11 is >= 0.

Note that any variable in an LP file that does not appear in the "Bounds" section is implicitly >=0 by the LP file specifications. Maybe you did not consider that when creating the LP file?

Please also see this chapter in the user manual for how to deal with models that are unexpectedly infeasible.