I am currently upgrading an azure functions project to dotnet 5. However, at some point I began having this error, and even doing a git reset --hard back to the last known-working version of the project (on dotnet 5) did not resolve it.
A host error has occurred during startup operation 'a515fa31-c9e5-466f-90f2-74916746168a'.
[2021-09-02T16:59:04.983Z] Microsoft.Azure.WebJobs.Extensions.FunctionMetadataLoader: The file '-SNIP-\bin\output\worker.config.json' was not found.
Value cannot be null. (Parameter 'provider')
I checked \bin\output and there is in fact no worker.config.json file.
The problem persists using Visual Studio 2019 to launch the project AND when using func host start --verbose --csharp
I have dotnet SDKs 3.1.412 and 5.0.400 installed.