# Mathlink.jl installation issue on Windows 10

**URL:** <https://discourse.julialang.org/t/mathlink-jl-installation-issue-on-windows-10/67217>\
**Category:** General Usage\
**Created:** [August 28, 2021, 12:10pm UTC](https://discourse.julialang.org/t/mathlink-jl-installation-issue-on-windows-10/67217 "2021-08-28T12:10:07Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Shuvomoy\_Das\_Gupta](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/shuvomoy_das_gupta/32/10069_2.png) [@Shuvomoy\_Das\_Gupta](https://discourse.julialang.org/u/Shuvomoy_Das_Gupta)\
**Post date:** [August 28, 2021, 12:10pm UTC](https://discourse.julialang.org/t/mathlink-jl-installation-issue-on-windows-10/67217/1 "2021-08-28T12:10:07Z")

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Dear All,

I am trying to install [MathLink.jl](https://github.com/JuliaInterop/MathLink.jl) on Windows 10. I have a full version of Mathematica 12.3, but I do not think it contains any “libML64.dll/ libML32.dll” file as mentioned in ReadMe. The closest is `ml64i4.dll` located in `C:\Program Files\Wolfram Research\Mathematica\12.3\SystemFiles\Links\MathLink\DeveloperKit\Windows-x86-64\SystemAdditions` and I set this folder as `MathLink dynamic library`.

However, after installation when I run `using MathLink`, I get the error

```julia
ERROR: LoadError: could not load library "C:\Program Files\Wolfram Research\Mathematica\12.3\SystemFiles\Links\MathLink\DeveloperKit\Windows-x86-64\SystemAdditions"
The specified module could not be found.
Stacktrace:
 [1] open!(link::MathLink.Link, args::String)
   @ MathLink C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\link.jl:25
 [2] _defaultlink()
   @ MathLink C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\link.jl:51
 [3] #weval#18
   @ C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\eval.jl:52 [inlined]
 [4] weval
   @ C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\eval.jl:52 [inlined]
 [5] #weval#19
   @ C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\eval.jl:53 [inlined]
 [6] weval
   @ C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\eval.jl:53 [inlined]
 [7] parseexpr(str::String)
   @ MathLink C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\eval.jl:63
 [8] var"@W_cmd"( __source__ ::LineNumberNode, __module__ ::Module, str::Any)
   @ MathLink C:\Users\shuvo\.julia\packages\MathLink\f5mIR\src\eval.jl:68
in expression starting at REPL[25]:1

```

Can anyone give me some hints/tips regarding how to work around this issue?

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<div class="post-metadata">

**Author:** ![genkuroki](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/genkuroki/32/18030_2.png) [@genkuroki](https://discourse.julialang.org/u/genkuroki)\
**Post date:** [August 28, 2021, 6:06pm UTC](https://discourse.julialang.org/t/mathlink-jl-installation-issue-on-windows-10/67217/2 "2021-08-28T18:06:38Z")

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I don’t use MathLink.jl now, but my note when I did use it says

> The README of [MathLink.jl](https://github.com/JuliaInterop/MathLink.jl) says to set JULIA\_MATHLINK to the path of the library named “libML64.dll/libML32.dll on Windows”, but in my environment I had to set it to the path of ml64i4.dll.

I set the environment variable as follows:

```julia
JULIA_MATHKERNEL = C:\Program Files\Wolfram Research\Wolfram Engine\12.0\MathKernel.exe
JULIA_MATHLINK = C:\Program Files\Wolfram Research\Wolfram Engine\12.0\SystemFiles\Links\MathLink\DeveloperKit\Windows-x86-64\SystemAdditions\ml64i4.dll

```

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<div class="post-metadata">

**Author:** ![Shuvomoy\_Das\_Gupta](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/shuvomoy_das_gupta/32/10069_2.png) [@Shuvomoy\_Das\_Gupta](https://discourse.julialang.org/u/Shuvomoy_Das_Gupta)\
**Post date:** [August 28, 2021, 7:56pm UTC](https://discourse.julialang.org/t/mathlink-jl-installation-issue-on-windows-10/67217/3 "2021-08-28T19:56:25Z")

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Your solution worked, thanks @genkuroki !