Or Tools Not Recognizing XPRESS Solver

[Darren Pham]

Hey, I've been trying to use Google OR to front end a fico xpress solver. However, I keep getting the error 

WARNING: Logging before InitGoogleLogging() is written to STDERR
W0617 14:32:12.881604 15908 linear_solver.cc:621] Support for XPRESS_LP not linked in, or the license was not found.

The most success I've had so far was with Google Or Tool's stable branch yet it still falls to this error. The license works fine when ran by itself.
Steps done so far (with Google OR stable branch):
1) Added find_package_handle_standard_args(XPRESS DEFAULT_MSG XPRESS_LIBRARIES XPRESS_INCLUDE_DIRS) to FindXPRESS.cmake
2) Configured build with cmake -S. -Bbuild -DBUILD_DEPS:BOOL=ON -DUSE_XPRESS=ON -DXPRESS_ROOT=C:\xpressmp -DBUILD_PYTHON=ON -DXPRESS_LIBRARIES=C:\xpressmp\lib -DXPRESS_INCLUDE_DIRS=C:\xpressmp\include
3) cmake --build build --target python_package -v
4) cd build; cd python;
5) python setup.py bdist_wheel
6) python -m pip install --user --find-links=dist ortools
I can create a GLOP solver and use it just as fine (glop is a built in solver) but for a 3rd party solver like XPRESS, no luck. When I run ctest -R "python_.*" -C Release, all the python tests pass (unsure if xpress solver is called upon to check during those tests).

I'm using Windows 10 64 bit. Xpress version 8.14

[PC See]

I am facing the same problem

" ... Support for xpress not linked in, or the license was not found ... "

Is there a solution already?

[Arvind Kumar]

This is a known issue, and we faced the same. The problem is that Google OR-tools is built with only Open Source solver support only by default. To use xpress (or cplex) you need to build or-tools from scratch. Steps here: https://developers.google.com/optimization/install/python/source_linux

[PC See]

Noted, thanks!