# Error building PyCall in Windows 10

**URL:** <https://discourse.julialang.org/t/error-building-pycall-in-windows-10/36455>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [March 24, 2020, 5:39pm UTC](https://discourse.julialang.org/t/error-building-pycall-in-windows-10/36455 "2020-03-24T17:39:56Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![sbacelar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sbacelar/32/4359_2.png) [@sbacelar](https://discourse.julialang.org/u/sbacelar)\
**Post date:** [March 24, 2020, 5:39pm UTC](https://discourse.julialang.org/t/error-building-pycall-in-windows-10/36455/1 "2020-03-24T17:39:56Z")

</div>

When I try to build PyCall in Julia 1.4 I get:

> (@v1.4) pkg\> build PyCall  
> Building Conda ─→ `C:\Users\sbac\.julia\packages\Conda\3rPhK\deps\build.log`  
> Building PyCall → `C:\Users\sbac\.julia\packages\PyCall\zqDXB\deps\build.log`  
> ┌ Error: Error building `PyCall`:  
> │ ┌ Info: Using the Python distribution in the Conda package by default.  
> │ └ To use a different Python version, set ENV[“PYTHON”]=“pythoncommand” and re-run Pkg.build(“PyCall”).  
> │ [ Info: Downloading miniconda installer …  
> │ ┌ Error: Download failed: curl: (35) schannel: next InitializeSecurityContext failed: Unknown error (0x80092012) - The revocation function was unable to  
> check revocation for the certificate.  
> │ └ @ Base download.jl:43  
> │ ERROR: LoadError: failed process: Process(`'C:\Windows\System32\curl.exe' -s -S -g -L -f -o 'C:\Users\sbac\.julia\conda\3\installer.exe' https://repo.co ntinuum.io/miniconda/Miniconda3-latest-Windows-x86_64.exe`, ProcessExited(35)) [35]  
> │  
> │ Stacktrace:  
> │ [1] pipeline\_error at .\process.jl:525 [inlined]  
> │ [2] download\_curl(::String, ::String, ::String) at .\download.jl:44  
> │ [3] download at .\download.jl:62 [inlined]  
> │ [4] \_install\_conda(::String, ::Bool) at C:\Users\sbac.julia\packages\Conda\3rPhK\src\Conda.jl:164  
> │ [5] \_install\_conda(::String) at C:\Users\sbac.julia\packages\Conda\3rPhK\src\Conda.jl:155  
> │ [6] runconda(::Cmd, ::String) at C:\Users\sbac.julia\packages\Conda\3rPhK\src\Conda.jl:112  
> │ [7] add(::String, ::String; channel::String) at C:\Users\sbac.julia\packages\Conda\3rPhK\src\Conda.jl:188  
> │ [8] add at C:\Users\sbac.julia\packages\Conda\3rPhK\src\Conda.jl:187 [inlined] (repeats 2 times)  
> │ [9] top-level scope at C:\Users\sbac.julia\packages\PyCall\zqDXB\deps\build.jl:84  
> │ [10] include(::String) at .\client.jl:439  
> │ [11] top-level scope at none:5  
> │ in expression starting at C:\Users\sbac.julia\packages\PyCall\zqDXB\deps\build.jl:43  
> └ @ Pkg.Operations D:\buildbot\worker\package\_win64\build\usr\share\julia\stdlib\v1.4\Pkg\src\Operations.jl:892

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<div class="post-metadata">

**Author:** ![stevengj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/stevengj/32/71_2.png) [@stevengj](https://discourse.julialang.org/u/stevengj)\
**Post date:** [March 24, 2020, 6:30pm UTC](https://discourse.julialang.org/t/error-building-pycall-in-windows-10/36455/2 "2020-03-24T18:30:56Z")

</div>

If you google the error message `"InitializeSecurityContext failed" julia` you will find several discussions, e.g. this one:

> [@Problem with curl.exe (Windows) and package installation](https://discourse.julialang.org/t/problem-with-curl-exe-windows-and-package-installation/29525/59):
>
> 4 months after I started this post, and many Windows updates, the problem with curl.exe continues as of Julia version 1.3.1 cry julia\> using Pkg julia\> Pkg.add("IJulia") Cloning default registries into `C:\Users\aerde\.julia` Cloning registry from "https://github.com/JuliaRegistries/General.git" Added registry `General` to `C:\Users\aerde\.julia\registries\General` Resolving package versions... Installed VersionParsing ── v1.2.0 Installed SoftGlobalScope ─ v1.0.10 Installed Ze…

TLDR: you have a broken `curl` on your system.

PS. please [quote code and output with backticks](https://discourse.julialang.org/t/psa-how-to-quote-code-with-backticks/7530).

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<div class="post-metadata">

**Author:** ![sbacelar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sbacelar/32/4359_2.png) [@sbacelar](https://discourse.julialang.org/u/sbacelar)\
**Post date:** [March 24, 2020, 6:53pm UTC](https://discourse.julialang.org/t/error-building-pycall-in-windows-10/36455/3 "2020-03-24T18:53:46Z")

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“Solved” by pausing my anti-virus for a minute and then doing `build PyCall`.