# No executable found for solver 'ipopt

I know that there are some questions concerning this type of error, for example, this link.

I first installed the latest version of ipopt through command line into my Pyomo environment and got the "No executable found for solver 'ipopt' " error. But after studying the stackoverflow answers, I realized that I should downgrade the version of ipopt afterwards I got the same error, again when implementing a model in Pyomo.

Here is the information:

And this is the error:

WARNING: Could not locate the 'ipopt' executable, which is required for solver
ipopt

---------------------------------------------------------------------------
ApplicationError                          Traceback (most recent call last)
<ipython-input-14-44d48836faac> in <module>
----> 1 results = opt.solve(model)

~\anaconda3\lib\site-packages\pyomo\opt\base\solvers.py in solve(self, *args, **kwds)
514         """ Solve the problem """
515
--> 516         self.available(exception_flag=True)
517         #
518         # If the inputs are models, then validate that they have been

~\anaconda3\lib\site-packages\pyomo\opt\solver\shellcmd.py in available(self, exception_flag)
116             if exception_flag:
117                 msg = "No executable found for solver '%s'"
--> 118                 raise ApplicationError(msg % self.name)
119             return False
120         return True

ApplicationError: No executable found for solver 'ipopt'


Now, I don't know what to do.

• Did you try finding out where ipopt is installed on your machine (search for its executable) and then, as described in the SO link, manually put it in the folder of pyomo to see whether this solves your problem? If that does, you know it's about setting the correct path for the solver. You can also try to pass the path of the solver executable to pyomo.
– EhsanK
Oct 7 at 17:35
• @EhsanK I installed the ipopt in the pyomo environment. Do you mean that? Oct 7 at 17:39
• The packages are saved somewhere on your machine. e.g. C:\Users\envs\solvers\ipotp. Search for the ipopt.exe on your machine and see where you can find it. Then either provide that path to pyomo as the solver path or just as a hack, do what you found on the SO link and paste it in the folder of solvers for pyomo. Check some of the available solvers in pyomo (like 'glpk', 'cbc', or some commercial solvers if you have them like 'gurobi') as explained here to learn where pyomo search for the path of the solvers.
– EhsanK
Oct 8 at 12:55
• @EhsanK Dear EhsanK, I managed to solve a model using ipopt. I copied the path of ipopt.exe in the system environment afterward I've smoothly use Pyomo. Thank you so much for your time. Oct 9 at 17:15