# Problem with \`\`Unsatisfiable requirements detected for package"
**URL:** https://discourse.julialang.org/t/problem-with-unsatisfiable-requirements-detected-for-package/42992
**Category:** New to Julia
**Created:** [July 13, 2020, 6:32pm UTC](https://discourse.julialang.org/t/problem-with-unsatisfiable-requirements-detected-for-package/42992 "2020-07-13T18:32:59Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@iamsuddhasattwa](https://discourse.julialang.org/u/iamsuddhasattwa)
#### Post date: [July 13, 2020, 6:32pm UTC](https://discourse.julialang.org/t/problem-with-unsatisfiable-requirements-detected-for-package/42992/1 "2020-07-13T18:32:59Z")
I am using Julia version 1.1.0 on a Windows computer. When I try to install the `Permutations.jl` package (listed [here](https://github.com/scheinerman/Permutations.jl)), I get the following error. What should I do ? I cannot even interpret the error message.
```julia
julia> Pkg.add("Permutations")
Resolving package versions...
ERROR: Unsatisfiable requirements detected for package Permutations [2ae35dd2]:
Permutations [2ae35dd2] log:
├─possible versions are: 0.3.0-0.3.2 or uninstalled
├─restricted to versions * by an explicit requirement, leaving only versions 0.3.0-0.3.2
└─restricted by compatibility requirements with Combinatorics [861a8166] to versions: uninstalled — no versions left
└─Combinatorics [861a8166] log:
├─possible versions are: [0.7.0, 1.0.0] or uninstalled
└─restricted to versions 1.0.0 by an explicit requirement, leaving only versions 1.0.0
Stacktrace:
[1] #propagate_constraints!#61(::Bool, ::Function, ::Pkg.GraphType.Graph, ::Set{Int64}) at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\GraphType.jl:1005
[2] propagate_constraints! at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\GraphType.jl:946 [inlined]
[3] #simplify_graph!#121(::Bool, ::Function, ::Pkg.GraphType.Graph, ::Set{Int64}) at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\GraphType.jl:1460
[4] simplify_graph! at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\GraphType.jl:1460 [inlined] (repeats 2 times)
[5] resolve_versions!(::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}, ::Nothing) at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\Operations.jl:371
[6] resolve_versions! at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\Operations.jl:315 [inlined]
[7] #add_or_develop#63(::Array{Base.UUID,1}, ::Symbol, ::Function, ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\Operations.jl:1171
[8] #add_or_develop at .\none:0 [inlined]
[9] #add_or_develop#15(::Symbol, ::Bool, ::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}, ::Function, ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\API.jl:54
[10] #add_or_develop at .\none:0 [inlined]
[11] #add_or_develop#14 at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\API.jl:31 [inlined]
[12] #add_or_develop at .\none:0 [inlined]
[13] #add_or_develop#13 at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\API.jl:29 [inlined]
[14] #add_or_develop at .\none:0 [inlined]
[15] #add_or_develop#12(::Base.Iterators.Pairs{Symbol,Symbol,Tuple{Symbol},NamedTuple{(:mode,),Tuple{Symbol}}}, ::Function, ::String) at C:\cygwin\home\Administrator\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.1\Pkg\src\API.jl:28
[16] add(::String) at .\none:0
[17] top-level scope at none:0
```
---
### Author:  [@StevenSiew](https://discourse.julialang.org/u/StevenSiew)
#### Post date: [July 14, 2020, 1:10pm UTC](https://discourse.julialang.org/t/problem-with-unsatisfiable-requirements-detected-for-package/42992/2 "2020-07-14T13:10:52Z")
> [@iamsuddhasattwa](#):
>
> `Combinatorics`
What version of Combinatorics do you have?
```julia
using Pkg
Pkg.status("Combinatorics")
```
Permutations
```julia
name = "Permutations"
uuid = "2ae35dd2-176d-5d53-8349-f30d82d94d4f"
author = ["Edward Scheinerman "]
version = "0.4.0"
[deps]
Combinatorics = "861a8166-3701-5b0c-9a16-15d98fcdc6aa"
LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
[compat]
julia = "1"
Combinatorics = "1.0"
```
---
### Author:  [@iamsuddhasattwa](https://discourse.julialang.org/u/iamsuddhasattwa)
#### Post date: [July 14, 2020, 1:34pm UTC](https://discourse.julialang.org/t/problem-with-unsatisfiable-requirements-detected-for-package/42992/3 "2020-07-14T13:34:32Z")
> [@StevenSiew](#):
>
> `Pkg.status("Combinatorics")`
My Combinatoics version is 1.0.0, as shown below
```julia-auto
julia> Pkg.status("Combinatorics")
Status `C:\Users\iamsu\.julia\environments\v1.1\Project.toml`
[861a8166] Combinatorics v1.0.0
```
I was unable to understand the purpose of the other things that you wrote, due to my lack of knowledge about version conflict resolution ☹ . I would be grateful if you could provide a few more words of explanation.
---
### Author:  [@heliosdrm](https://discourse.julialang.org/u/heliosdrm)
#### Post date: [July 14, 2020, 3:38pm UTC](https://discourse.julialang.org/t/problem-with-unsatisfiable-requirements-detected-for-package/42992/4 "2020-07-14T15:38:55Z")
There is something that does not let you install the latest verison of Permutations.jl (0.4.0). The error message you are receiving tells:
```julia
possible versions are: 0.3.0-0.3.2 or uninstalled
```
Those versions are not compatible with Combinatorics 1.0 (besides being quite old), so you can’t install it along with it.
There may be another package in your environment that – directly or indirectly – does not allow Permutations 0.4.0. You may [try in a new environment](https://julialang.github.io/Pkg.jl/v1/environments/)