Develop Reference

Issue in .net6 gRPC project template [duplicate]

I have a multi-project solution with Prism Nuget packages installed in several projects. I then attempted to add a Prism Mef extensions package to one of the projects using the Nuget Package Manager UI (I have already added it to one of the other projects).
The first time I attempted to add the package, it failed to install one of the dependencies, no specific error reason, just "failed". So, I installed it a second time, all seemed to be fine, no errors reported, but a few of the references did not resolve.
So, I uninstalled the package and all dependencies and installed it again. Again all appeared fine, but more references do not resolve.
I have tried uninstalling and installing the package more times but get the same result every time now.
I have had this problem many times and I know its not specific to the Prism package as I've had it with loads of different packages.
I think its just a major bug with Nuget, but I'm hoping somebody will know an easy way to fix it. I think I usually have better success with the Nuget console, but I find it more effort to use.
I've done some searching online and not really found a good explanation of the cause of the problem or a way to resolve it.
Somebody at work completely refuses to have anything to do with Nuget as he has so many of these issues, but I am determined to make it work!

Within the Package Manager Console run the following command:
Update-Package -reinstall
This will reinstall each nuget package within that project which should resolve any missing references.
If you know you're missing a specific reference:
Update-Package -reinstall <Package-Name>

I just closed Visual Studio and reopened it and references are resolved...!

You need to follow this procedure.
1. Update-Package -reinstall
2. Restart visual studio.

You may want to check the .NET version of the package vs. your project.
I had an instance where my project was .NET 4.6.1, and the package I was attempting to install was using version 4.6.2. After updating my project to the same .NET version, the reference showed up.

I recently encountered this error on visual studio 2012, solution for me was to delete .nupkg file from nuget cache. Nuget cache location can be found from nuget settings > general > browse.
Note: I did not clear cache, I just deleted a specific file from cache directory and reinstalled the nuget package.

Delete all the <assemblyBinding> references from your .config file, then run this command from the Nuget Package Manager:
Get-Project -All | Add-BindingRedirect

This is how I fixed it.
I was working on a legacy .NET framework project (using <Reference Include... rather than PackageReference). The .dlls were referenced with a relative path that wasn't being resolved.
Fixed by changing to absolute paths, building, then changing back to the original relative paths.
For example:
<Reference Include="My.Package">
<HintPath>..\..\packages\My.Package.dll</HintPath>
</Reference>
Changed to:
<Reference Include="My.Package">
<HintPath>C:\Users\will\Documents\MySolution\packages\My.Package.dll</HintPath>
</Reference>
Then built and changed back to the relative path and the build still worked.

In our case, on one machine VS was holding onto an old version of a dependency, so references to newly added methods in the dependency were not resolving (even when package manager was reporting the latest version installed). The solution was to restart visual after uninstalling the dependency, then install again.

After clone of web site project nuget restores packages but references are not found VS 2015

We have moved a legacy web site to git in TFS, and anytime the project is cloned nugget restores the packages per the package.config, and adds them to the packages folder. The subsequent build fails due to not being able to find the assemblies added through the nuget restore.
If you do a update-package -reinstall and the project builds successfully. Is this expected behavior or do I have a setup issue? The previous repo had the packages being checked in to eliminate this issue but I'd like to avoid that.

Is this expected behavior or do I have a setup issue?
Yes, this is expected behavior for NuGet, so do not worry that it is a setup problem.
NuGet Restore only restores files in the packages directory (\packages folder ), but does not restore files inside your project or otherwise modify your project. For example, if a package has added some reference DLLs or other files in your project, if you delete any of these files, they will not be re-added when restoring this package. This may cause the your project to not be able to find the missing dependencies when building.
Besides, the expected result is that the references should be used normally without broken after restore packages. In this case, we will not need to spend extra time using update-package -reinstall command line to uninstall and reinstall packages.
So use the "Update-Package -reinstall" command to force reinstall the package references and content files into project in order to resolve those references that were broken after packages restore.

NuGet has problems with missing packages, how to restore?

When I try to compile my program I get the following error:
This project references NuGet package(s) that are missing on this computer. Enable NuGet Package Restore to download them. For more information, see http://go.microsoft.com/fwlink/?LinkID=317567.
Now when I right click on the solution and press
All packages are already installed and there is nothing to restore.
I tried manually reinstalling every package which didn't solve the problem, I tried reinstalling NuGet but that didn't help either and I even tried reinstalling visual studio.
I also tried moving the package folder from the tfs folder to overwrite my package folder but that didn't solve anything. I also tried redownloading them with this package missing, that didn' t solve the problem either.
Anybody know how to restore the nuget packages?

Use Package Manager Console in Visual Studio to run this command.
1.This will restore all packages from solution
nuget restore YourSolution.sln
2.If you want to reinstall the packages to the same versions as were previously installed
Update-Package -reinstall

Honestly, whoever developed the NuGet command for VS needs to go back to the drawing board. They totaly missed the fact that sometimes these DLL(s) and/or files get corrupt or deleted. a "NuGet Get-Packages -Force" option would really save their bacon. The only GAP I see is that VS and the Package console does not allow you to invoke a forced download from NuGet. Even clearing the cache via VS is useless.

I ran into this issue when I tried to build my project on a computer where the packages-folder did not already exist in the solution root.
When the project file was initially created, it seems VS2019 added the following into the project file:
<Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
<PropertyGroup>
<ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them. For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
</PropertyGroup>
<Error Condition="!Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.2.0.1\build\net46\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.2.0.1\build\net46\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props'))" />
</Target>
From what I understand those settings are deprecated nowadays, no idea why VS inserted it in the first place.
Anyway, after removing those lines VS restored the packages and built the solution correctly again.

It's probably a good idea to clear the Nuget Cache by deleting the contents within this directory: C:\Users\{your_username}\AppData\Local\NuGet

All you need is that:
Open the Package Manager Console and run this command: Update-Package -reinstall
P.S: VS2017 and above NuGet Package Manager is included with Visual Studio, no need to install anything else.

The problem with the functionality of the NuGet package can also be caused by the fact that NuGet package is requiring certain dependency that the project does not meet.
NuGet package can have a declared dependency in Dependecies section, e.g. .NETFramework,Version=v.4.6.2 while the project is targeted to an older version (Target framework: .NET Framework 4.6.1.).
Instead of the NuGet system notifying the user of this fact, the project simply does not compile.

In my case, I have different Nuget configurations, and somehow the HintPath in the project file didn't fit.
Maybe you should check if the HintPath leads to the right NuGetPackages folder.
You should also check the following entries at the top of the file:
And at the bottom of the file:
All these paths should point to the right NuGetPackage folder in your file structure.

In my case the problem was solved by deleting the "obj" folder(s) and then rebuilding the solution.
The "obj" folder had several NuGet related files that still referred to version 0.0.2 of a package while all projects in the solution were already using version 1.0.0 of that package. Building the solution failed with the error message "package with version 0.0.2 could not be found". The solution with build folders included was recently copied from another machine.

Well it's probably a bad way but I found that it works if I just delete the line
http://go.microsoft.com/fwlink/?LinkID=317567." HelpKeyword="BCLBUILD2001" />
from the project.csproj , not sure if this is going to cause problems later on but it works for now.

The "Microsoft.CodeAnalysis.BuildTasks.Csc" task could not be loaded from the assembly

I have a project that I have on TFS online. When Im trying to build the project, I get the following error:
Severity Code Description Project File Line
Error The "Microsoft.CodeAnalysis.BuildTasks.Csc" task could not be loaded from the assembly C:\Users\Bryan\Source\Workspaces\TestProject\ContosoUniversity\packages\Microsoft.Net.Compilers.1.0.0\build..\tools\Microsoft.Build.Tasks.CodeAnalysis.dll. Could not load file or assembly 'file:///C:\Users\Bryan\Source\Workspaces\TestProject\ContosoUniversity\packages\Microsoft.Net.Compilers.1.0.0\tools\Microsoft.Build.Tasks.CodeAnalysis.dll' or one of its dependencies. Could not find the file. Confirm that the declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask. ContosoUniversity
Has this something to do with that Azure don't support ASP.NET 4.6?

Here was the fix for me. Using Nuget Package Manager, remove these two packages if referenced:
Microsoft.CodeDom.Providers.DotNetCompilerPlatform
Microsoft.Net.Compilers
After that, run a rebuild. This ensured that the build was not trying to use a specific build exe. Click here for the Diff against previous revision

No, it is not related to Azure Web Apps doesn't support ASP.NET 4.6. Actually, you get this error message because NuGet packages are checked into version control.
So, you need to remove folder TestProject\ContosoUniversity\packages from TFS and build again. See: BuildTasks.Csc task could not be loaded from the assembly?

I had the same problem sometime ago, to fix it:
make sure your packages are not under source control
Force restore all package, by deleting the package folder
restart your visual studio

In my case it got resolved by updating the below two Nuget packages to the latest version:
Microsoft.CodeDom.Providers.DotNetCompilerPlatform
Microsoft.Net.Compilers

Delete the packages folder or its contents, clean, rebuild solves the problem for me.

If you take a look at the file in reference it points you to a packages location. It turns out that NuGet packages is broken
To Resolve: you simply need to delete that packages folder (usually under project name \ project name \ packages.), then on build, Nuget will restore all the required packages.

I needed to update all my Nuget packages on my development box, then check the project in to TFS again.
For added peace of mind, I deleted the packages folder in the Team City build folder.

In case someone looks at this later on.
I was getting this issue only when building in DevOps.
But after manually deleting packages in my local build I started getting the same issue locally.
After removing the apparently missing NuGets using the NuGet manager the issue resolved it's self both locally and on azure.
Not sure what caused it but might save someone a headache in the future.
I was using .net 4.7.2

Nuget Packages not working correctly in Visual Studio

I am writing a Windows Phone app, at the beggining using VS 2010 Express for windows phone. Then I installed VS 2012 and i made a desktop app which consumed JSON/REST service using RestSharp. Due to lack of support for plugins in Express version, i got full VS 2010 Ultimate and installed Nuget. When I create a win phone library project, and i add a RestSharp package, it shows in References, but i cannot access any of it's classes (and using RestSharp is underlined in red color). Also, when i Remove it and add again from Add Reference i get an Incompatible reference error window:
RestSharp.WindowsPhone, Version=103.2.0.0, Culture=neutral, PublicKeyToken=null" is incompatible with
Windows Phone 7.1
In order to add it yourself you should to change the project's terget to a compatible framework first.
It also appears if i change the target to WP 7.0.
Has anyone solved similar problem?

In my case this was because there was a packages.config file in the project folder but not in the solution. This was why I could not add the reference again properly. Delete this file from the physical disk, and re-run your Install-Package command. It should add this correctly now.

Are you using source control?
The it might be possible that you have not yet set the solution to enable package restore (NuGet documentation).
Right click on the Solution node in Solution Explorer and select
Enable NuGet Package Restore.
After that Solution Explorer will contain a few items more and there will be a new folder packages that was automatically added to your solution folder. You will need this folder to add to your version control because it will contain your installed NuGet packages.
That's it.
If you want to know more, here's more details on what it (automatically) does for you:
It added a solution folder named .nuget containing NuGet.exe and a
NuGet.targets MsBuild file. It also changed every project in the
solution to import the NuGet.targets MsBuild task.
With this in place, any time a project is compiled, the build task
will look at each project's packages.config file and for each package
in that file, ensure that the corresponding package exists within the
packages folder. For any missing package, the build task will download
and unpack the package.
In the restore scenario, NuGet will grab the exact version when
restoring a package. It will not perform any upgrades.
Additionally, if you have the latest NuGet version installed, will now find a new option unter Tools -> Options... -> Package Manager -> General -> Allow NuGet to download missing packages during build that I would also suggest to use.
The name says it all. If the solution is configured to use a certain NuGet package but the package is not yet installed on your development machine, NuGet will download it automatically for you when you do your next build.