# Problem installing packages

**URL:** <https://discourse.julialang.org/t/problem-installing-packages/11090>\
**Category:** General Usage\
**Created:** [May 23, 2018, 6:43am UTC](https://discourse.julialang.org/t/problem-installing-packages/11090 "2018-05-23T06:43:13Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![tfk17lstm](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tfk17lstm](https://discourse.julialang.org/u/tfk17lstm)\
**Post date:** [May 23, 2018, 6:43am UTC](https://discourse.julialang.org/t/problem-installing-packages/11090/1 "2018-05-23T06:43:13Z")

</div>

Dear colleagues,

I am trying to install different solvers for JuMP but I am getting this errors:

```julia
Pkg.add("Ipopt")
INFO: Cloning cache of Ipopt from https://github.com/JuliaOpt/Ipopt.jl.git
INFO: Installing Ipopt v0.3.0
INFO: Building Ipopt
WARNING: imported binding for srcdir overwritten in module __anon__
Info: Downloading https://github.com/staticfloat/IpoptBuilder/releases/download/v3.12.8-9/Ipopt.x86_
64-w64-mingw32.tar.gz to C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\usr\downloads\Ipopt.x86_64
-w64-mingw32.tar.gz...
Exception setting "SecurityProtocol": "Cannot convert null to type "System.Net.SecurityProtocolType
" due to invalid enumeration values. Specify one of the following enumeration values and try again.
 The possible enumeration values are "Ssl3, Tls"."
At line:1 char:35
+ [System.Net.ServicePointManager]:: <<<< SecurityProtocol =
    + CategoryInfo : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : PropertyAssignmentException

Exception calling "DownloadFile" with "2" argument(s): "The underlying connection was closed: An un
expected error occurred on a send."
At line:4 char:24
+ $webclient.DownloadFile <<<< ("https://github.com/staticfloat/IpoptBuilder/releases/download/v3.1
2.8-9/Ipopt.x86_64-w64-mingw32.tar.gz", "C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\usr\downl
oads\Ipopt.x86_64-w64-mingw32.tar.gz")
    + CategoryInfo : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

==========================================[ERROR: Ipopt]==========================================

LoadError: Could not download https://github.com/staticfloat/IpoptBuilder/releases/download/v3.12.8-
9/Ipopt.x86_64-w64-mingw32.tar.gz to C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\usr\downloads\
Ipopt.x86_64-w64-mingw32.tar.gz
while loading C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\build.jl, in expression starting on l
ine 13

====================================================================================================

==========================================[BUILD ERRORS]==========================================

WARNING: Ipopt had build errors.

 - packages with build errors remain installed in C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6
 - build the package(s) and all dependencies with `Pkg.build("Ipopt")`
 - build a single package by running its `deps/build.jl` script

====================================================================================================

```

Also, I have try to use the Pkg.build I get:

```julia

julia> Pkg.build("Ipopt")
INFO: Building Ipopt
WARNING: imported binding for srcdir overwritten in module __anon__
Info: Downloading https://github.com/staticfloat/IpoptBuilder/releases/download/v3.12.8-9/Ipopt.x86_
64-w64-mingw32.tar.gz to C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\usr\downloads\Ipopt.x86_64
-w64-mingw32.tar.gz...
Exception setting "SecurityProtocol": "Cannot convert null to type "System.Net.SecurityProtocolType
" due to invalid enumeration values. Specify one of the following enumeration values and try again.
 The possible enumeration values are "Ssl3, Tls"."
At line:1 char:35
+ [System.Net.ServicePointManager]:: <<<< SecurityProtocol =
    + CategoryInfo : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : PropertyAssignmentException

Exception calling "DownloadFile" with "2" argument(s): "The underlying connection was closed: An un
expected error occurred on a send."
At line:4 char:24
+ $webclient.DownloadFile <<<< ("https://github.com/staticfloat/IpoptBuilder/releases/download/v3.1
2.8-9/Ipopt.x86_64-w64-mingw32.tar.gz", "C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\usr\downl
oads\Ipopt.x86_64-w64-mingw32.tar.gz")
    + CategoryInfo : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

==========================================[ERROR: Ipopt]==========================================

LoadError: Could not download https://github.com/staticfloat/IpoptBuilder/releases/download/v3.12.8-
9/Ipopt.x86_64-w64-mingw32.tar.gz to C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\usr\downloads\
Ipopt.x86_64-w64-mingw32.tar.gz
while loading C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6\Ipopt\deps\build.jl, in expression starting on l
ine 13

====================================================================================================

==========================================[BUILD ERRORS]==========================================

WARNING: Ipopt had build errors.

 - packages with build errors remain installed in C:\JuliaPro-0.6.2.2\pkgs-0.6.2.2\v0.6
 - build the package(s) and all dependencies with `Pkg.build("Ipopt")`
 - build a single package by running its `deps/build.jl` script

====================================================================================================

```

I hope that you can help me.

---

<div class="post-metadata">

**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [May 23, 2018, 11:40am UTC](https://discourse.julialang.org/t/problem-installing-packages/11090/2 "2018-05-23T11:40:02Z")

</div>

This looks like the same issue as [Problems with CodecZlib](https://discourse.julialang.org/t/problems-with-codeczlib/10124)

Do the suggestions from that thread help in your case?