Paket Restore Failed with code 137

Published on Tuesday, January 3, 2023

This morning I thought I'd give learning the SAFE Stack a go. As a long standing C# developer I've been seeing more and more language features come in to the language from F#, so it makes sense to me to see if those features a better fit in their natural environment.

I checked that I had the correct dependencies for SAFE stack installed (.NET 6, Node), and then installed the SAFE template

dotnet new -i SAFE.Template

I created a new project with dotnet new SAFE, restored the tools required to build the project dotnet tool restore, and then ran the app with dotnet run

This resulted in the following error

error MSB3073: The command "dotnet paket restore" exited with code 137.

What is Paket?

Paket is an alternative dependency manager for .NET Projects, that has a few extra features over Nuget.

The principle reasoning behind Paket seems tro be that with Nuget, there is no way to see if a package is a direct dependency of a project, or a dependency that has been pulled in via a direct dependency, eg a transitive dependency, and that " If two packages reference conflicting versions of a package, NuGet will silently take the latest version."

Back to the error. Paket can be either installed globally on your machine, or local to a specific project. In the SAFE Stack template Paket is referenced as a local tool in the dotnet-tools.json file, and is installed locally when you run dotnet tool restore.

Googling the error didn't glean much and there was nothing in Paket's issues list with that specific error code. There was a suggestion I found on twitter that it might be caused by a conflict between .NET 5 and .NET 6, and removing .NET 5 might fix the issue. It did not.

What i should have done was save myself a few minutes and increased the verbosity of the dotnet run command with the --verbosity diagnostic switch. That gave a more detailed answer of Failed to initialize CoreCLR, HRESULT: 0x80004005 and that was in the Paket issues list with this answer

please note paket 7.1.3 still requires .NET 3.1 installed, even when your project is on higher SDK versions. Otherwise it will give the Failed to initialize CoreCLR, HRESULT: 0x80004005 error.

My Mac didn't have 3.1 on it, and installing it fixed the issue. Annoyingly, the dependencies for Paket does not list this as a requirement, the docs only say that 3.0 or higher is required.

TL;DR;

At the time of writing, Paket has a dependency on the .NET 3.1 SDK. If you don't have that installed on your machine, Paket will not work.