For the record, the full error message is
(@v1.5) pkg> add IJulia
Installing known registries into C:\Users\LENOVO\.julia
┌ Warning: could not download https://pkg.julialang.org/registries
└ @ Pkg.Types D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Types.jl:951
┌ Warning: could not download https://pkg.julialang.org/registries
└ @ Pkg.Types D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Types.jl:951
Cloning registry from “https://github.com/JuliaRegistries/General.git”
Added registry General to C:\Users\LENOVO\.julia\registries\General
Resolving package versions…
Cloning [739be429-bea8-5141-9913-cc70e7f3736d] MbedTLS from https://github.com/JuliaLang/MbedTLS.jl.git
Installed MbedTLS ───────── v1.0.2
Cloning [7073ff75-c697-5162-941a-fcdaad2a7d2a] IJulia from https://github.com/JuliaLang/IJulia.jl.git
Installed IJulia ────────── v1.21.4
Cloning [69de0a69-1ddd-5017-9359-2bf0b02dc9f0] Parsers from https://github.com/JuliaData/Parsers.jl.git
Installed Parsers ───────── v1.0.11
Cloning [c8ffd9c3-330d-5841-b78e-0817d7145fa1] MbedTLS_jll from https://github.com/JuliaBinaryWrappers/MbedTLS_jll.jl.git
Installed MbedTLS_jll ───── v2.16.8+0
Cloning [c2297ded-f4af-51ae-bb23-16f91089e4e1] ZMQ from https://github.com/JuliaInterop/ZMQ.jl.git
Installed ZMQ ───────────── v1.2.1
Cloning [682c06a0-de6a-54ab-a142-c8b1cf79cde6] JSON from https://github.com/JuliaIO/JSON.jl.git
Installed JSON ──────────── v0.21.1
Cloning [81def892-9a0e-5fdd-b105-ffc91e053289] VersionParsing from https://github.com/JuliaInterop/VersionParsing.jl.git
Installed VersionParsing ── v1.2.0
Cloning [8f1865be-045e-5c20-9c9f-bfbfb0764568] ZeroMQ_jll from https://github.com/JuliaBinaryWrappers/ZeroMQ_jll.jl.git
Installed ZeroMQ_jll ────── v4.3.2+4
Cloning [8f4d0f93-b110-5947-807f-2305c1781a2d] Conda from https://github.com/JuliaPy/Conda.jl.git
Installed Conda ─────────── v1.4.1
Cloning [b85f4697-e234-5449-a836-ec8e2f98b302] SoftGlobalScope from https://github.com/stevengj/SoftGlobalScope.jl.git
Installed SoftGlobalScope ─ v1.1.0
Downloading artifact: MbedTLS
Exception calling “DownloadFile” with “2” argument(s): “İşlem zaman aşımına uğradı”
At line:12 char:1
$webclient.DownloadFile("https://pkg.julialang.org/artifact/a5355b4ef …
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : WebException
Downloading artifact: MbedTLS
Exception calling “DownloadFile” with “2” argument(s): “İşlem zaman aşımına uğradı”
At line:7 char:1
$webclient.DownloadFile("https://github.com/JuliaBinaryWrappers/MbedT …
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : WebException
ERROR: Unable to automatically install ‘MbedTLS’ from 'C:\Users\LENOVO.julia\packages\MbedTLS_jll\qGMUr\Artifacts.toml’Stacktrace:
[1] error(::String) at .\error.jl:33
[2] ensure_artifact_installed(::String, ::Dict{String,Any}, ::String; platform::Pkg.BinaryPlatforms.Platform, verbose::Bool, quiet_download::Bool) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Artifacts.jl:898
[3] ensure_all_artifacts_installed(::String; platform::Pkg.BinaryPlatforms.Platform, pkg_uuid::Nothing, include_lazy::Bool, verbose::Bool, quiet_download::Bool) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Artifacts.jl:962
[4] download_artifacts(::Pkg.Types.Context, ::Array{String,1}; platform::Pkg.BinaryPlatforms.Windows, verbose::Bool) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Operations.jl:663
[5] download_artifacts(::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}; platform::Pkg.BinaryPlatforms.Windows, verbose::Bool) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Operations.jl:642
[6] add(::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}, ::Array{Base.UUID,1}; preserve::Pkg.Types.PreserveLevel, platform::Pkg.BinaryPlatforms.Windows) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\Operations.jl:1141
[7] add(::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}; preserve::Pkg.Types.PreserveLevel, platform::Pkg.BinaryPlatforms.Windows, kwargs::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\API.jl:188
[8] add(::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\API.jl:139
[9] #add#21 at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\API.jl:67 [inlined]
[10] add(::Array{Pkg.Types.PackageSpec,1}) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\API.jl:67
[11] do_cmd!(::Pkg.REPLMode.Command, ::REPL.LineEditREPL) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\REPLMode\REPLMode.jl:404
[12] do_cmd(::REPL.LineEditREPL, ::String; do_rethrow::Bool) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\REPLMode\REPLMode.jl:382
[13] do_cmd at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\REPLMode\REPLMode.jl:377 [inlined]
[14] (::Pkg.REPLMode.var"#24#27"{REPL.LineEditREPL,REPL.LineEdit.Prompt})(::REPL.LineEdit.MIState, ::Base.GenericIOBuffer{Array{UInt8,1}}, ::Bool) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\Pkg\src\REPLMode\REPLMode.jl:546
[15] #invokelatest#1 at .\essentials.jl:710 [inlined]
[16] invokelatest at .\essentials.jl:709 [inlined]
[17] run_interface(::REPL.Terminals.TextTerminal, ::REPL.LineEdit.ModalInterface, ::REPL.LineEdit.MIState) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\REPL\src\LineEdit.jl:2355
[18] run_frontend(::REPL.LineEditREPL, ::REPL.REPLBackendRef) at D:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.5\REPL\src\REPL.jl:1144
[19] (::REPL.var"#38#42"{REPL.LineEditREPL,REPL.REPLBackendRef})() at .\task.jl:356
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