# Gurobi does not work any more in Pyomo after getting a new license

I have been using Pyomo with a free Academic license for Gurobi and so far it worked quite well. Now my license expired and I received a new license that is stored in the folder

"C:/Gurobi/gurobi.lic"

However, when I now run Pyomo I get the error message:

"ApplicationError: Solver (gurobi) did not exit normally"

and the error is thrown by the last of the following lines:

solver = pyo.SolverFactory('gurobi')
solver.options['MIPGap'] = 0.1
solver.options['TimeLimit'] = 100
solution = solver.solve(model, tee=True)


Do you have any idea why I now get this error? The license itself should be okay according to the Gurobi website (it expires in 2022). I just downloaded it to the before mentioned folder as recommended by Gurobi. Do I have to do anything else?

I'd appreciate every comment.

Update: Here is the full error message:

runfile('C:/Users/wi9632/bwSyncShare3/Eigene Arbeit/Code/Python/Demand_Side_Management/Building_1_mHP_EV.py', wdir='C:/Users/wi9632/bwSyncShare3/Eigene Arbeit/Code/Python/Demand_Side_Management')
Traceback (most recent call last):

File "C:\Users\wi9632\bwSyncShare3\Eigene Arbeit\Code\Python\Demand_Side_Management\Building_1_mHP_EV.py", line 589, in <module>
solution = solver.solve(model, tee=True)

File "C:\Users\wi9632\Anaconda3\envs\tf\lib\site-packages\pyomo\opt\base\solvers.py", line 602, in solve
"Solver (%s) did not exit normally" % self.name)

ApplicationError: Solver (gurobi) did not exit normally

• Peter - Can you please open a support request with Gurobi? It looks like there is an issue with your license. Thanks. Jul 2 at 14:30

This does not look like a license issue. This is a Pyomo error code. You should share some more info about the error message and other output before. If your new license is stored in C:\gurobi\gurobi.lic, Gurobi will find the license automatically and there is usually nothing else required to make it work.

Update: To test the license, it is better to either run gurobi_cl from the full Gurobi installation or running this little Python code if only gurobipy is installed:

import gurobipy as gp
m = gp.Model()
m.optimize()

• Thanks mattmitlen for your comment. I added the full error message in the question. Basically last weak everything worked fine but then I had to renew my license. I just did what is told at the Gurobi website (download the license into the folder C:\gurobi\gurobi.lic) via the Windows command prompt. There it was said that there is alreay a license at that path and I decided to overwrite it. Since then, I get this error message on every Pyomo model that I have. Jun 29 at 12:46
• Any comments to my last comment? I'd highly appreciate every further comment from you. Jun 30 at 14:03
• I just updated my answer. Hope that helps. Jun 30 at 20:27
• Thanks for your answer mattmilten. When using your suggested code I get the error message "ModuleNotFoundError: No module named 'gurobipy'" Jul 1 at 8:10
• Basically I do not understand why Gurobi does not work anymore in my installation. As said before, one week ago everything was perfect but the license expired. After that I renewed it and did exactly what is told at the Gurobi website (run a command on windows prompt). The strange thing is that I get a message in the windows command prompt that everything was successfull and the new license is stored at a certain location. However, when running a Pyomo model I get the error message ApplicationError: Solver (gurobi) did not exit normally Jul 1 at 8:13

You need to put the new licence in your terminal and run it

Installation To install this license on a computer where Gurobi Optimizer is installed, copy and paste the following command to the Start/Run menu (Windows only) or a command/terminal prompt (any system like mac):

Let's assume your licence is as follows

grbgetkey 58eab684-cd60-12eb-b669-0242ac120002


The grbgetkey command requires an active internet connection.

• Thanks Optimization team for your answer. What do you mean by terminal and how can I put the licence file there and run it? Jun 29 at 9:37
• I guess PeterBe is using Windows instead of Linux because he mentioned C:/Gurobi/gurobi.lic. Erh. Linux is usually better than windows in terms of performance. Jun 29 at 15:45
• Thanks Optimization team for your answer. Basically I had already done what you suggested before posting my question. I just did it again. The problem still exists. Basically last weak everything worked fine but then I had to renew my license. I just did what is told at the Gurobi website but now I get this error message. Jun 30 at 7:43
• C:\WINDOWS\System32>grbgetkey 61e390b2-d587-11eb-8dc0-0242ac130004 info : grbgetkey version , build v9.1.1rc0 info : Contacting Gurobi license server... info : License file for license ID 656694 was successfully retrieved info : License expires at the end of the day on 2022-06-20 info : Saving license file... In which directory would you like to store the Gurobi license file? [hit Enter to store it in C:\Users\wi9632]: A license file already exists in 'C:\Users\wi9632\gurobi.lic' Continue? [Y/n] info : License 656694 written to file C:\Users\wi9632\gurobi.lic Jun 30 at 7:44
• Here is the output of the command prompt in Windows. Basically it just tells that everything was okay and a new license is saved. I can also find the license file. What else do I have to do in order to activate the license? Jun 30 at 7:47

thanks for all your answers. I just wanted to say that the problem was in fact related to the Gurobi license file. I contacted Gurobi and they could reproduce the error and they just gave me a new license. Now everything is okay again.