# A question about my Gurobi

**URL:** <https://discourse.julialang.org/t/a-question-about-my-gurobi/75369>\
**Category:** General Usage\
**Tags:** question\
**Created:** [January 28, 2022, 1:52pm UTC](https://discourse.julialang.org/t/a-question-about-my-gurobi/75369 "2022-01-28T13:52:17Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![abcde](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/abcde/32/16180_2.png) [@abcde](https://discourse.julialang.org/u/abcde)\
**Post date:** [January 28, 2022, 1:52pm UTC](https://discourse.julialang.org/t/a-question-about-my-gurobi/75369/1 "2022-01-28T13:52:18Z")

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Why can’t my Gurobi install??

(@v1.6) pkg\> build Gurobi  
Building Gurobi → `C:\Users\dell\.julia\scratchspaces\44cfe95a-1eb2-52ea-b672-e2afdf69b78f\0c39671e531549c2969bdf0c0513d03a07f9ffd8\build.log`  
ERROR: Error building `Gurobi`:  
ERROR: LoadError: Unable to locate Gurobi installation. If the advice above did not help,  
open an issue at [https://github.com/jump-dev/Gurobi.jl](https://github.com/jump-dev/Gurobi.jl) and post the full  
print-out of this diagnostic attempt.

Stacktrace:  
[1] error(s::String)  
@ Base .\error.jl:33  
[2] top-level scope  
@ C:\Users\dell.julia\packages\Gurobi\Dn7m0\deps\build.jl:161  
[3] include(fname::String)  
@ Base.MainInclude .\client.jl:444  
[4] top-level scope  
@ none:5  
in expression starting at C:\Users\dell.julia\packages\Gurobi\Dn7m0\deps\build.jl:155

**Unable to locate Gurobi installation. Running some common diagnostics.**

Gurobi.jl only supports the following versions:

- gurobi91
- gurobi90

Did you download and install one of these versions from [gurobi.com](http://gurobi.com)?  
Installing Gurobi.jl via the Julia package manager is _not_ sufficient!

Found GUROBI\_HOME = C:\gurobi950\win64

Does this point to the correct install location?

We’re going to look for the Gurobi library in this directory:  
C:\gurobi950\win64\bin

That directory has the following files:

- C:\gurobi950\win64\bin\Gurobi95.NET.XML
- C:\gurobi950\win64\bin\Gurobi95.NET.dll
- C:\gurobi950\win64\bin\GurobiJni95.dll
- C:\gurobi950\win64\bin\grb\_ts.exe
- C:\gurobi950\win64\bin\grbcluster.exe
- C:\gurobi950\win64\bin\grbgetkey.exe
- C:\gurobi950\win64\bin\grbprobe.exe
- C:\gurobi950\win64\bin\grbtune.exe
- C:\gurobi950\win64\bin\gurobi.bat
- C:\gurobi950\win64\bin\gurobi95.dll
- C:\gurobi950\win64\bin\gurobi95\_light.dll
- C:\gurobi950\win64\bin\gurobi\_cl.exe
- C:\gurobi950\win64\bin\vslauncher.exe
- C:\gurobi950\win64\bin\vswhere.exe

We were looking for (but could not find) a file named like  
`libgurobiXXX.so`, `libgurobiXXX.dylib`, or `gurobiXXX.dll`.

You should set the `GUROBI_HOME` environment variable to point to the  
install location then try again. For example (updating the path to the  
correct location if needed):

```julia
# On Windows, this might be
ENV["GUROBI_HOME"] = "C:\\Program Files\\gurobi910\\win64\\"
import Pkg
Pkg.add("Gurobi")
Pkg.build("Gurobi")

# On OSX, this might be
ENV["GUROBI_HOME"] = "/Library/gurobi910/mac64/"
import Pkg
Pkg.add("Gurobi")
Pkg.build("Gurobi")

# On Unix, this might be
ENV["GUROBI_HOME"] = "/opt/gurobi910/linux64/"
import Pkg
Pkg.add("Gurobi")
Pkg.build("Gurobi")

```

**Note: your path may differ. Check which folder you installed the Gurobi  
binary in, and update the path accordingly.**

thanks！

---

<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 28, 2022, 5:28pm UTC](https://discourse.julialang.org/t/a-question-about-my-gurobi/75369/2 "2022-01-28T17:28:38Z")

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Probably the `Gurobi.jl` version you are trying to install does not recognize the `95` in `gurobi95.dll` as a valid version. Did you try to force Julia to install `Gurobi.jl` 0.10.1? (i.e., the most recent version.)