# Old version (1.0.5) can't find BenchmarkTools in General registry
**URL:** https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288
**Category:** General Usage
**Created:** [March 19, 2026, 1:15pm UTC](https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288 "2026-03-19T13:15:49Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Benny](https://discourse.julialang.org/u/Benny)
#### Post date: [March 19, 2026, 1:15pm UTC](https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288/1 "2026-03-19T13:15:49Z")
I’m trying to compare something on v1.12.5 with 1.0.5, but I immediately hit a snag on adding BenchmarkTools to the version environment. AFAIK BenchmarkTools does have versions in the General registry that is compatible with Julia 1.0, so is this an old registry tweak I have to do manually?
```julia-auto
(v1.0) pkg> add BenchmarkTools
ERROR: The following package names could not be resolved:
* BenchmarkTools (not found in project, manifest or registry)
Please specify by known `name=uuid`.
(v1.0) pkg> add BenchmarkTools@1.5
ERROR: The following package names could not be resolved:
* BenchmarkTools (not found in project, manifest or registry)
Please specify by known `name=uuid`.
(v1.0) pkg> add BenchmarkTools=6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf
Resolving package versions...
ERROR: Unsatisfiable requirements detected for package BenchmarkTools [6e4b80f9]:
BenchmarkTools [6e4b80f9] log:
├─BenchmarkTools [6e4b80f9] has no known versions!
└─restricted to versions * by an explicit requirement — no versions left
```
---
### Author:  [@ufechner7](https://discourse.julialang.org/u/ufechner7)
#### Post date: [March 19, 2026, 1:33pm UTC](https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288/2 "2026-03-19T13:33:38Z")
Julia 1.0 cannot understand the current registry format. You need to do:
```julia-auto
mv ~/.julia/registries/General.tar.gz ~/.julia/registries/General.tar.gz.bak
mv ~/.julia/registries/General.toml ~/.julia/registries/General.toml.bak
git clone https://github.com/JuliaRegistries/General.git ~/.julia/registries/General
```
Then, this should work:
```julia-auto
julia +1.0
```
And in Julia:
```julia-auto
using Pkg
Pkg.add("BenchmarkTools")
```
---
### Author:  [@Benny](https://discourse.julialang.org/u/Benny)
#### Post date: [March 19, 2026, 2:55pm UTC](https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288/3 "2026-03-19T14:55:33Z")
Just to check some things before I pull the trigger, that looks like I’m backing up the compressed registry I already have, then cloning the registry’s repo. Is that right? Is the rationale that the compressed registry does not contain the necessary information but the repo does? Do I reverse this with `registry rm General` and `registry add General`?
---
### Author:  [@ufechner7](https://discourse.julialang.org/u/ufechner7)
#### Post date: [March 19, 2026, 3:07pm UTC](https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288/4 "2026-03-19T15:07:31Z")
> [@Benny](#):
>
> Is the rationale that the compressed registry does not contain the necessary information but the repo does?
Both contain the same information, but in a different format.
You can revert this with the commands:
```julia-auto
pkg> registry rm General
pkg> registry add General
```
---
### Author:  [@GunnarFarneback](https://discourse.julialang.org/u/GunnarFarneback)
#### Post date: [March 19, 2026, 3:32pm UTC](https://discourse.julialang.org/t/old-version-1-0-5-cant-find-benchmarktools-in-general-registry/136288/5 "2026-03-19T15:32:31Z")
> [@Benny](#):
>
> Just to check some things before I pull the trigger, that looks like I’m backing up the compressed registry I already have, then cloning the registry’s repo. Is that right?
Actually it’s better not to rename those files. Then sufficiently new Julia will use the compressed registry and old Julia will use it from git.