I have not heard that this error can occur when all CPLEX licenses are in
use. If that is the case then you should find that the problem disappears
as soon as the number of current CPLEX users decreases.
Bob Fourer
4...@ampl.com
The MPS format is defined only for linear problems, so it cannot be used to represent an SOCP.
From within AMPL you can invoke some features of CPLEX's conflict refiner. See the section "Directives for Handling Infeasible Problems" in the User's Guide at
http://www.ampl.com/BOOKLETS/amplcplex122userguide.pdf
Bob Fourer