I had some issue in compiling DifferentialEquations after an update so I removed it re-add it. Here is the output. Please see the last couple of lines.
(v1.1) pkg> st
Status `C:\Users\Himanshi\.julia\environments\v1.1\Project.toml`
[c52e3926] Atom v0.10.1
[6e4b80f9] BenchmarkTools v0.4.3
[a134a8b2] BlackBoxOptim v0.5.0
[336ed68f] CSV v0.5.12
[49dc2e85] Calculus v0.5.0
[324d7699] CategoricalArrays v0.6.0
[9961bab8] Cbc v0.6.4
[944b1d66] CodecZlib v0.6.0
[a93c6f00] DataFrames v0.19.4
[1313f7d8] DataFramesMeta v0.5.0
[864edb3b] DataStructures v0.17.0
[e7dc6d0d] DataValues v0.4.12
[7806a523] DecisionTree v0.8.3
[39dd38d3] Dierckx v0.4.1
[1130ab10] DiffEqParamEstim v1.8.0
[0c46a032] DifferentialEquations v6.6.0
[31c24e10] Distributions v0.21.1
[f6369f11] ForwardDiff v0.10.3
[38e38edf] GLM v1.1.1
[60bf3e95] GLPK v0.11.3
[28b8d3ca] GR v0.41.0
[09f84164] HypothesisTests v0.8.0
[7073ff75] IJulia v1.20.0
[b6b21f68] Ipopt v0.6.0
[8c755ed3] JuML v0.0.0 [`C:\Users\Himanshi\.julia\dev\JuML`]
[4076af6c] JuMP v0.20.0
[aa1ae85d] JuliaInterpreter v0.7.2
[e5e0dc1b] Juno v0.7.2
[5ab0869b] KernelDensity v0.5.1
[b964fa9f] LaTeXStrings v1.0.3
[fcefd6c4] LambdaFn v0.3.0
[50d2b5c4] Lazy v0.14.0
[093fc24a] LightGraphs v1.3.0
[2fda8390] LsqFit v0.8.1
[33e6dc65] MKL v0.0.0 #master (https://github.com/JuliaComputing/MKL.jl)
[cc2ba9b6] MLDataUtils v0.5.0
[1914dd2f] MacroTools v0.5.1
[b8f27783] MathOptInterface v0.9.2
[961ee093] ModelingToolkit v0.6.4
[2774e3e8] NLsolve v4.1.0
[2bd173c7] NodeJS v0.6.0
[429524aa] Optim v0.19.2
[9b87118b] PackageCompiler v0.6.4
[ce6b1742] RDatasets v0.6.1
[731186ca] RecursiveArrayTools v1.0.2
[295af30f] Revise v2.1.10
[3646fa90] ScikitLearn v0.5.1
[90137ffa] StaticArrays v0.11.0
[2913bbd2] StatsBase v0.32.0
[f3b207a7] StatsPlots v0.12.0
[70df011a] TableReader v0.4.0
[bd369af6] Tables v0.2.11
[a759f4b9] TimerOutputs v0.5.0
[c17dfb99] WinRPM v0.4.2
[c2297ded] ZMQ v1.0.0
[ade2ca70] Dates
[8bb1440f] DelimitedFiles
[8ba89e20] Distributed
[de0858da] Printf
[9a3f8284] Random
[2f01184e] SparseArrays
[10745b16] Statistics
[8dfed614] Test
(v1.1) pkg> rm DifferentialEquations
Updating `C:\Users\Himanshi\.julia\environments\v1.1\Project.toml`
[0c46a032] - DifferentialEquations v6.6.0
Updating `C:\Users\Himanshi\.julia\environments\v1.1\Manifest.toml`
[764a87c0] - BoundaryValueDiffEq v2.3.0
[bcd4f6db] - DelayDiffEq v5.14.0
[5a0ffddc] - DiffEqFinancial v2.1.0
[c894b116] - DiffEqJump v6.2.1
[77a26b50] - DiffEqNoiseProcess v3.3.1
[055956cb] - DiffEqPhysics v3.2.0
[0c46a032] - DifferentialEquations v6.6.0
[c619ae07] - DimensionalPlotRecipes v0.2.0
[f9640e96] - MultiScaleArrays v1.5.0
[e409e4f3] - PoissonRandom v0.4.0
[e6cf234a] - RandomNumbers v1.3.0
[ae5879a3] - ResettableStacks v0.6.0
[9672c7b4] - SteadyStateDiffEq v1.5.0
[789caeaf] - StochasticDiffEq v6.9.1
[c3572dad] - Sundials v3.7.0
(v1.1) pkg> gc
Active manifests:
`C:\Users\Himanshi\.julia\environments\v1.1\Manifest.toml`
Deleted `C:\Users\Himanshi\.julia\packages\BoundaryValueDiffEq\XvS8h` (22.807 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DelayDiffEq\nHoER` (148.554 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DiffEqFinancial\V11wE` (8.722 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DiffEqJump\vTKOd` (127.416 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DiffEqNoiseProcess\SCC7m` (54.845 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DiffEqPhysics\DppQ4` (29.909 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DifferentialEquations\4jSpr` (479.235 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\DimensionalPlotRecipes\JfuWg` (6.315 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\MultiScaleArrays\1LixA` (58.805 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\PoissonRandom\Ohb1g` (12.772 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\RandomNumbers\URH3g` (251.488 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\ResettableStacks\esu9D` (7.061 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\SteadyStateDiffEq\q0UMK` (9.644 KiB)
Deleted `C:\Users\Himanshi\.julia\packages\StochasticDiffEq\e0qFK` (1.023 MiB)
Deleted `C:\Users\Himanshi\.julia\packages\Sundials\CRi5j` (25.481 MiB)
Deleted 15 package installations (27.692 MiB)
(v1.1) pkg> gc
Active manifests:
`C:\Users\Himanshi\.julia\environments\v1.1\Manifest.toml`
Deleted 0 package installations
(v1.1) pkg> add DifferentialEquations
Updating registry at `C:\Users\Himanshi\.julia\registries\General`
Updating git-repo `https://github.com/JuliaRegistries/General.git`
Resolving package versions...
Installed SteadyStateDiffEq ────── v1.5.0
Installed ResettableStacks ─────── v0.6.0
Installed DimensionalPlotRecipes ─ v0.2.0
Installed BoundaryValueDiffEq ──── v2.3.0
Installed Sundials ─────────────── v3.7.0
Installed DiffEqPhysics ────────── v3.2.0
Installed DifferentialEquations ── v6.6.0
Installed OrdinaryDiffEq ───────── v5.16.0
Installed DiffEqFinancial ──────── v2.2.0
Installed DiffEqBase ───────────── v6.0.0
Installed RandomNumbers ────────── v1.3.0
Installed PoissonRandom ────────── v0.4.0
Installed DiffEqOperators ──────── v4.1.0
Installed DiffEqJump ───────────── v6.2.1
Installed StochasticDiffEq ─────── v6.7.0
Installed MultiScaleArrays ─────── v1.5.0
Installed DiffEqNoiseProcess ───── v3.3.1
Installed DelayDiffEq ──────────── v5.14.0
Updating `C:\Users\Himanshi\.julia\environments\v1.1\Project.toml`
[0c46a032] + DifferentialEquations v6.6.0
Updating `C:\Users\Himanshi\.julia\environments\v1.1\Manifest.toml`
[764a87c0] + BoundaryValueDiffEq v2.3.0
[bcd4f6db] + DelayDiffEq v5.14.0
[2b5f629d] ↑ DiffEqBase v5.20.1 ⇒ v6.0.0
[5a0ffddc] + DiffEqFinancial v2.2.0
[c894b116] + DiffEqJump v6.2.1
[77a26b50] + DiffEqNoiseProcess v3.3.1
[9fdde737] + DiffEqOperators v4.1.0
[055956cb] + DiffEqPhysics v3.2.0
[0c46a032] + DifferentialEquations v6.6.0
[c619ae07] + DimensionalPlotRecipes v0.2.0
[f9640e96] + MultiScaleArrays v1.5.0
[1dea7af3] ↑ OrdinaryDiffEq v5.15.1 ⇒ v5.16.0
[e409e4f3] + PoissonRandom v0.4.0
[e6cf234a] + RandomNumbers v1.3.0
[ae5879a3] + ResettableStacks v0.6.0
[9672c7b4] + SteadyStateDiffEq v1.5.0
[789caeaf] + StochasticDiffEq v6.7.0
[c3572dad] + Sundials v3.7.0
Building Sundials → `C:\Users\Himanshi\.julia\packages\Sundials\CRi5j\deps\build.log`
julia> using DifferentialEquations
[ Info: Precompiling DifferentialEquations [0c46a032-eb83-5123-abaf-570d42b7fbaa]
┌ Warning: Package DiffEqFinancial does not have Markdown in its dependencies:
│ - If you have DiffEqFinancial checked out for development and have
│ added Markdown as a dependency but haven't updated your primary
│ environment's manifest file, try `Pkg.resolve()`.
│ - Otherwise you may need to report an issue with DiffEqFinancial
└ Loading Markdown into DiffEqFinancial from project dependency, future warnings for DiffEqFinancial are suppressed.
┌ Warning: The call to compilecache failed to create a usable precompiled cache file for DifferentialEquations [0c46a032-eb83-5123-abaf-570d42b7fbaa]
│ exception = Required dependency DiffEqFinancial [5a0ffddc-d203-54b0-88ba-2c03c0fc2e67] failed to load from a cache file.
└ @ Base loading.jl:969
[ Info: Recompiling stale cache file C:\Users\Himanshi\.julia\compiled\v1.1\DiffEqFinancial\RxltQ.ji for DiffEqFinancial [5a0ffddc-d203-54b0-88ba-2c03c0fc2e67]
┌ Warning: Package DiffEqFinancial does not have Markdown in its dependencies:
│ - If you have DiffEqFinancial checked out for development and have
│ added Markdown as a dependency but haven't updated your primary
│ environment's manifest file, try `Pkg.resolve()`.
│ - Otherwise you may need to report an issue with DiffEqFinancial
└ Loading Markdown into DiffEqFinancial from project dependency, future warnings for DiffEqFinancial are suppressed.
julia>