# Difficulty installing Ipopt

**URL:** <https://discourse.julialang.org/t/difficulty-installing-ipopt/8303>\
**Category:** General Usage\
**Created:** [January 12, 2018, 5:31am UTC](https://discourse.julialang.org/t/difficulty-installing-ipopt/8303 "2018-01-12T05:31:02Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Curious1](https://avatars.discourse-cdn.com/v4/letter/c/41988e/32.png) [@Curious1](https://discourse.julialang.org/u/Curious1)\
**Post date:** [January 12, 2018, 5:31am UTC](https://discourse.julialang.org/t/difficulty-installing-ipopt/8303/1 "2018-01-12T05:31:02Z")

</div>

I want to install Ipopt package but when I run `Pkg.build("Ipopt")` , it throws the following error.

```julia
/opt/JuliaPro/JuliaPro-0.5.2.2/JuliaPro/pkgs-0.5.2.2/v0.5/Ipopt/deps/src/Ipopt-3.12.1/Ipopt/src/Interfaces/.libs/libipopt.so: undefined reference to `dgetrf2_'
/opt/JuliaPro/JuliaPro-0.5.2.2/JuliaPro/pkgs-0.5.2.2/v0.5/Ipopt/deps/src/Ipopt-3.12.1/Ipopt/src/Interfaces/.libs/libipopt.so: undefined reference to `dpotrf2_'
collect2: error: ld returned 1 exit status
make[3]: *** [ipopt] Error 1
make[2]: *** [all-recursive] Error 1
make[1]: *** [all-recursive] Error 1
make: *** [all-recursive] Error 1

```

Please help me, I need it urgently.