# Julia 0.5.1 Pkg.update() throwing error

**URL:** <https://discourse.julialang.org/t/julia-0-5-1-pkg-update-throwing-error/3518>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [May 4, 2017, 4:53pm UTC](https://discourse.julialang.org/t/julia-0-5-1-pkg-update-throwing-error/3518 "2017-05-04T16:53:36Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![udion](https://avatars.discourse-cdn.com/v4/letter/u/9dc877/32.png) [@udion](https://discourse.julialang.org/u/udion)\
**Post date:** [May 4, 2017, 4:53pm UTC](https://discourse.julialang.org/t/julia-0-5-1-pkg-update-throwing-error/3518/1 "2017-05-04T16:53:36Z")

</div>

I have downloaded Julia 0.5.1 and on doing Pkg.update() I am getting the following error

```julia
ERROR: unknown package Observables required by WebDisplay
 in requirements(::Dict{String,Base.Pkg.Types.VersionSet}, ::Dict{String,Base.Pkg.Types.Fixed}, ::Dict{String,Dict{VersionNumber,Base.Pkg.Types.Available}}) at ./pkg/query.jl:11
 in resolve(::Dict{String,Base.Pkg.Types.VersionSet}, ::Dict{String,Dict{VersionNumber,Base.Pkg.Types.Available}}, ::Dict{String,Tuple{VersionNumber,Bool}}, ::Dict{String,Base.Pkg.Types.Fixed}, ::Dict{String,VersionNumber}, ::Set{String}) at ./pkg/entry.jl:477
 in update(::String, ::Set{String}) at ./pkg/entry.jl:458
 in (::Base.Pkg.Dir.##2#3{Array{Any,1},Base.Pkg.Entry.#update,Tuple{String,Set{String}}})() at ./pkg/dir.jl:31
 in cd(::Base.Pkg.Dir.##2#3{Array{Any,1},Base.Pkg.Entry.#update,Tuple{String,Set{String}}}, ::String) at ./file.jl:59
 in #cd#1(::Array{Any,1}, ::Function, ::Function, ::String, ::Vararg{Any,N}) at ./pkg/dir.jl:31
 in update() at ./pkg/pkg.jl:210Preformatted text

```

 ![](https://global.discourse-cdn.com/julialang/original/3X/e/f/ef86cc92d6407cd38bd1091c0b35240d4131842c.png)

I have tried cloning [https://github.com/JuliaGizmos/Observables.jl](https://github.com/JuliaGizmos/Observables.jl)  
but I’m getting the following error

 ![](https://global.discourse-cdn.com/julialang/original/3X/9/a/9a4afc76e5142e299bbe75cc8eb2ddce24cd0117.png)

Kindly help me resolve this.

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<div class="post-metadata">

**Author:** ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)\
**Post date:** [May 4, 2017, 8:43pm UTC](https://discourse.julialang.org/t/julia-0-5-1-pkg-update-throwing-error/3518/2 "2017-05-04T20:43:15Z")

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Looks like the same problem as

> [@DifferentialEquations Pkg won't be added](https://discourse.julialang.org/t/differentialequations-pkg-wont-be-added/3194):
>
> julia\> versioninfo() Julia Version 0.5.1 Commit 6445c82 (2017-03-05 13:25 UTC) Platform Info: OS: Linux (x86\_64-pc-linux-gnu) CPU: Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz WORD\_SIZE: 64 BLAS: libopenblas (USE64BITINT DYNAMIC\_ARCH NO\_AFFINITY Haswell) LAPACK: libopenblas64\_ LIBM: libopenlibm LLVM: libLLVM-3.7.1 (ORCJIT, haswell) I was struggling in a combat between Bio and DifferentialEquations, which were trying to downgrade each other. Finally, I decided to initialize the Pkg i…

It’s a bug in the Pkg resolver. The fix will be Julia v0.5.2 and v0.6, which should be released shortly (the PRs are already open for them):

> <https://github.com/JuliaLang/julia/pull/21684>

> <https://github.com/JuliaLang/julia/pull/21694>
>
> will run pkgeval here, make sure we aren't introducing any regressions relative …to beta
> (5d609ec44c3f3c2a3bc40d47e0979ebbf1ba5d29 is a non-backport commit, for this reason)

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<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 4, 2017, 10:02pm UTC](https://discourse.julialang.org/t/julia-0-5-1-pkg-update-throwing-error/3518/3 "2017-05-04T22:02:00Z")

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You _may_ be able to work around the issue by telling the package resolver to try harder:

```julia
julia> ENV["JULIA_PKGRESOLVE_ACCURACY"] = 10

julia> Pkg.update()

```

You may also want to uninstall any packages which you are no longer using.

But as Chris says, the real fix will be coming in the next versions of Julia itself.