EF Core add-migration Build Failed

Question

I have a developer that is getting "Build failed." when running add-migration in a .NET Core EF project, with no explanation of why the build failed. How do you troubleshoot this error?

This is what he gets in the Package Manager Console:

Additional information:

We have a few other developers using the same solution code (myself included) that have not issues with add-migration.

This is what I see in Package Manager Console:

We've verified that the project builds, and the entire solution builds. We've done "dotnet restore" and rebuild all multiple times, in addition to restarting VS2015. We've verified that the correct default solution is selected both in Solution Explorer, and in the Package Manager Console drop-down. We've verified that he has the correct SDK installed on his machine. I'm at a loss as to what to check next...any time I've had a failure during add-migration I've gotten enough information to point me in the direction of what to check, but just "Build failed." is a fairly useless error output.

You should try to use the -v option and see if you get more details about the error. — anserk, Jun 27 '17 at 16:55
When I get build errors on just a single machine, I start be deleting personal solution file (.suo). You will need to reset the startup project after that. — Steve Greene, Jun 27 '17 at 17:05
We used the -v option, we did not get more details about the error. — jceddy, Jun 27 '17 at 18:37
execute "dotnet build" command and see more details about the error. — Rahmat Anjirabi, Sep 19 '19 at 19:31
The -v option helped! A note to future travelers, you may want to redirect the output to a text file, the problem is probably near the top of the output. And -v, the verbose flag, means what it says. It is very, very verbose. — Chris Baker, Nov 05 '20 at 16:35

score 123 · Answer 1 · edited Feb 20 '18 at 10:40

123

It's because of other projects in your solutions. e.g If you have two projects in your solution as Project A and Project B. If Project A is not successful build and then Project B data migration will fail. So you should unload Project A and add the migration to Project B again.

I think this is not a good answer but hope this help.

edited Feb 20 '18 at 10:40

Vivek Nuna

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answered Sep 04 '17 at 16:06

Myo Min Han

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I had an unwanted database project in my solution which was added as a random test and I was not aware of it! When i built the solution, no error shown but the `add-migration` Build Failed! After i remove that temp project, everything works! – S.Serpooshan Nov 28 '18 at 11:17
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I had the `dotnet run watch` running and was holding everything up – whisk Mar 30 '20 at 21:06
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The easiest way to identify the problem: 1. open command-line 2. navigate to project folder where you want to add the migration 3. run `dotnet build` The output will show all errors and warnings – Elmar Jun 03 '20 at 08:21

score 50 · Answer 2 · edited Jul 15 '22 at 10:17

50

I had the exact same problem (.NET Core 2.0.1).

Sometimes it helps if the project is rebuilt.

I also encounter the problem when I opened the project in 2 Visual Studios.
Closing one Visual Studio fixed the error.

Ctrl + C (first stop the application from running, this alone might be enough!)
dotnet run build
dotnet ef migrations add InitialCreate

edited Jul 15 '22 at 10:17

Fabala Dibbasey

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answered Dec 12 '17 at 15:19

Makla

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Rebuilding the project after changing the connection string on the `appsettings.json` works for me. – John Isaiah Carmona Jan 03 '19 at 15:29
I had the solution open in VS2019 and simply closing VS2019 made the command work. – Christopher Aug 13 '19 at 00:10
I closed all open visual studios, it fixed. – Majid Azarniush Oct 18 '20 at 13:33

score 27 · Answer 3 · answered Mar 17 '20 at 17:29

I was struggling with this one while using Visual Studio 2019 version 16.5.0.

What solved it finally:

Close Visual Studio;
Reopen Visual Studio;
Make sure you right click the Solution if you have multiple projects and select Rebuild Solution.

Note that I tried doing a Rebuild Solution before and that did not catch the error. So it's important to close VS and reopen it.

It then showed the error that was causing add-migration command to fail with Build failed message.

thanks! simple ... it was just a matter of closing and reopening visual studio :) — Amir Dora., Apr 26 '20 at 11:19

score 23 · Answer 4 · answered Apr 12 '19 at 08:49

23

I suggest adding -v to have more info.

In my example, I had to add <LangVersion>latest</LangVersion> to my projects, as this was missing from some of them.

answered Apr 12 '19 at 08:49

Romain Vergnory

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score 18 · Answer 5 · edited Feb 17 '21 at 00:31

18

Try these steps:

Clean the solution.
Build every project separately.
Resolve any errors if found (sometimes, VS is not showing errors until you build it separately).
Then try to run migration again.

edited Feb 17 '21 at 00:31

Pang

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answered Nov 26 '18 at 13:23

Bharat chaudhari

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score 15 · Answer 6 · answered Apr 21 '18 at 21:09

15

In my situation it was the error

namespace aspnetcore does not exist .. are you missing a reference?

I have figured it out by adding the -v (or --verbose) flag to the dotnet ef command.

answered Apr 21 '18 at 21:09

Liam Kernighan

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adding -v saved me. – Romain Vergnory Apr 12 '19 at 08:48

score 12 · Answer 7 · edited Feb 17 '21 at 00:31

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In my case, the application was running. Apparently, it needs to be stopped. Weird error message anyways.

edited Feb 17 '21 at 00:31

Pang

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answered May 09 '19 at 18:08

Denis Nutiu

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Same. IISExpress was hosting my web. Closed VS2019 (which closes IISExpress) and the migration succeeded. – Christopher Aug 13 '19 at 00:23
Same here. I closed VS2022 and Sign out my PC (which closes every running program) then the migration succeeded – Mousa Al-Kalouti Sep 17 '22 at 18:55

score 10 · Answer 8 · edited Feb 17 '21 at 00:33

10

Had the same situation. This helped:

Open Package Manager Console

Change directory to Migrations folder:

cd C:\YourSolution\YourProjectWithMigrations

Enter in PM:

dotnet ef migrations add YourMigrationName

edited Feb 17 '21 at 00:33

Pang

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answered Feb 02 '18 at 09:15

Yaroslav

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score 10 · Answer 9 · edited Feb 17 '21 at 00:34

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Open Output window in Visual Studio and check your build log. In my case, even though my current configuration was Release, Add-Migration built the project in Debug, which had an error. For some reason, VS didn't display the error anywhere except Output window for me.

edited Feb 17 '21 at 00:34

Pang

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answered Jun 28 '18 at 08:28

Archeg

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Check in Output windows is professional way. We can know exact root cause why build failed. – Zin Min Apr 05 '19 at 09:51
So stupid of me not to think of it but there was no hint to look at that window (it was hidden by the PM Console.. But many thanks for mentioning it! – Erik Thysell May 05 '20 at 08:29

score 7 · Answer 10 · edited Jan 31 '20 at 16:23

7

Got the same error when I tried to run add-migration. Make sure that you don't have any syntax errors in your code.

I had a syntax error in my code, and after I fixed it, I was able to run add-migration.

edited Jan 31 '20 at 16:23

Fourat

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answered Dec 08 '19 at 17:29

Sara Onval

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I made some hefty changes to models and (re)building would not show any errors, but add-migration just said "Build failed". Running the command line yielded the actual errors: in this case it was the Razor **Views**! Fixed those and add-migration worked again. – GeoffM Sep 28 '22 at 22:32

score 3 · Answer 11 · answered Jul 30 '18 at 10:53

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Most likely that there is an existing error in your code. Try rebuilding first and correct all the errors.

Happened to me, I am trying to rollback migration but I have not corrected the errors in the code yet.

answered Jul 30 '18 at 10:53

Andy Parinas

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score 3 · Answer 12 · edited Feb 17 '21 at 00:35

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Just got into this issue. In my case, I was debugging my code and it was making my migrations fail.

Since in Visual Studio Code, the debugger is so low-profile (only a small bar), I didn't realize about this until I read some questions and decided to look better.

edited Feb 17 '21 at 00:35

Pang

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answered Apr 25 '19 at 14:58

andrescpacheco

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score 2 · Answer 13 · answered Jun 29 '17 at 22:59

I had exact same error but I am using Visual Studio Community 2017 Version 15.2 (26430.14) to build .Net Core projects.

I have a ASP.NET Core MVC web project and a separate security project using ASP.NET Core Identity. The web project contains connection string in aspsettings.json config file.

I also installed Bundler & Minifier and Web Essentials 2017 extensions in Visual Studio so that I can compile, minify and bundle my assets and put them to wwwroot.

I figured out it was the MSBuild those 2 extensions secretly download that caused the problem, because I had Enable Bundle on Build and Enable Compile on Build on. After I disable that, everything works fine.

Probably not the cause to your problem, but might be worthy to just give it a try.

score 2 · Answer 14 · answered Apr 19 '18 at 15:40

I think this happened to me when I tried to run dotnet ef migrations add xyz whilst it was already running.

In the end, just to be sure, I stopped the currently running instance, then ran it again to ensure it was rebuilt, stopped it again and I was able to run the dotnet ef migrations add command

score 2 · Answer 15 · edited Feb 17 '21 at 00:36

2

Try saving DataContext.cs first. It worked for me.

edited Feb 17 '21 at 00:36

Pang

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answered Oct 04 '18 at 20:12

davut temel

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score 2 · Answer 16 · answered Aug 20 '20 at 15:03

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In My case, add the package Microsoft.EntityFrameworkCore.Tools fixed problem

answered Aug 20 '20 at 15:03

Keti Kutateladze

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score 1 · Accepted Answer · answered Jun 27 '17 at 21:38

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The developer ended up un-mapping the project from TFS, deleting it, and re-mapping it. It's now working for him.

answered Jun 27 '17 at 21:38

jceddy

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This would be my *last* resort. – japes Sophey Mar 05 '19 at 11:52

score 1 · Answer 18 · answered Jun 29 '18 at 10:24

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I think the 2 commands below always work (if you run them at project's folder)

dotnet ef migrations add (database object fron ApplicationDbContextDBContext)
dotnet ef database update

answered Jun 29 '18 at 10:24

gbarel

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score 1 · Answer 19 · answered Aug 27 '18 at 17:23

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I had the same error. What I did, I corrected the error the one I have in code, and rebuilt the project. Then I ran the ms-dos command and it worked.

answered Aug 27 '18 at 17:23

ahmet bilgic

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score 1 · Answer 20 · answered Aug 16 '19 at 11:54

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I got the same error. There were no errors during the build proccess. I closed the Visual Studio and it worked.

answered Aug 16 '19 at 11:54

Imran Sh

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score 1 · Answer 21 · answered Dec 20 '19 at 10:51

I had the same problem when running: dotnet ef migrations add InitialCreate so what I did is tried to build the project using: dotnet build command.

It throws an error : Startup.cs(20,27): error CS0103: bla bla for example. which you can trace to find the error in your code.

Then i refactored the code and ran: dotnet build again to check any errors until there is no errors and build is succeded. Then ran: dotnet ef migrations add InitialCreate then the build succeded.

score 1 · Answer 22 · answered Apr 29 '20 at 16:19

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this is because deleting projects or class libraries from solution and adding projects after deleting with same name. best thing is delete solution file and add projects to it.this works for me (I did this using vsCode)

answered Apr 29 '20 at 16:19

pamal Sahan

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score 1 · Answer 23 · answered Aug 27 '20 at 13:00

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In my case I had couple of such errors:

The process cannot access the file 'C:\xxx\bin\Debug\netcoreapp3.1\yyy.dll' 
because it is being used by another process. [C:\zzz.csproj]

I was able to see those errors only after adding -v parameter.

The solution was to shutdown the Visual Studio and run the command again.

answered Aug 27 '20 at 13:00

infografnet

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Thanks for the "-v" switch. That helped! This poorly designed, manual EF solution by Microsoft means a million things can go wrong that block the "migration" junk files from getting built. In my case it didn't like some custom logging I was doing in my Main method. Who knew! Your -v or verbose allowed me to see all the errors and track it down. Otherwise this mess by Microsoft would have eaten up another half of my day :) – Stokely Nov 17 '20 at 03:18

score 0 · Answer 24 · answered Jul 28 '18 at 03:27

0

maybe it cause because of you did not add this in YOUR_PROJECT.csproj

<ItemGroup>

<DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.Dotnet" Version="2.0.2" />

answered Jul 28 '18 at 03:27

Farshad

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score 0 · Answer 25 · edited Jul 12 '23 at 16:20

Make sure you have code generation inside startup.cs. Also, make sure to use <TargetFramework> if you are using multiple target frameworks <TargetFrameworks>. You can temporary comment <TargetFrameworks> when running add-migration.

Also, if the PropertyGroup has Condition, you need to comment/remove them when running ef migration

Example

<Project Sdk="Microsoft.NET.Sdk.Web">

<PropertyGroup>
<TargetFramework>netcoreapp2.1</TargetFramework>
</PropertyGroup>

<ItemGroup>
<PackageReference Include="Microsoft.AspNetCore.App" />
 <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.2" />
<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.1.3" />
 </ItemGroup>

</Project>

score 0 · Answer 26 · answered Aug 09 '19 at 10:31

0

I got the same error. I fixed it by stopping the project build. After that it worked fine.

answered Aug 09 '19 at 10:31

lrefopam

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score 0 · Answer 27 · answered Dec 05 '19 at 09:33

Turns out this could also be caused by BuildEvents. For me I was referencing $(SolutionDir) there. With a regular build this variable has value, but running dotnet * commands is done at project level apparently. $(SolutionDir) comes out like Undefined in verbose mode (-v). This seems like a bug to me.

score 0 · Answer 28 · answered Dec 08 '19 at 09:50

0

1: I was getting the error: PM> Add-Migration "InitialDB" Build failed. 2:The error was the "(" missing. I corrected that and error is gone.

so the error you can see the error in the output. The error was because of the code issue.

answered Dec 08 '19 at 09:50

Mani

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score 0 · Answer 29 · answered Jan 16 '20 at 03:17

0

In my case it was failing because an unrelated project in the solution was failing. Unloading that project and running the command again worked.

answered Jan 16 '20 at 03:17

Pranav Raj

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score 0 · Answer 30 · answered Jan 17 '20 at 09:02

0

In my case it was because i had error somewhere.. Like missing coma in db config file, so VS didn't throw exception until build

So just try to run your code...

answered Jan 17 '20 at 09:02

Qhori

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This does not provide an answer to the question. Please ensure that your answer improves upon other answers already present in this question. – hongsy Jan 17 '20 at 09:34

score 0 · Answer 31 · answered May 10 '20 at 04:55

0

Same errors for me. I tried -v but nothing. Then I realised I had changed the model so much that the controller was showing errors.

Once I fixed the errors in the controller it worked.

answered May 10 '20 at 04:55

netchicken

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score 0 · Answer 32 · answered Jul 03 '20 at 04:02

It might have many possibilities I guess. In my case, it was due packages versions inbalance

I had

<PackageReference Include="Microsoft.EntityFrameworkCore" Version="3.1.1"/>
<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.3"/>

I just need it to downgrade the core Design package to 3.1.1 to match the upper core version

<PackageReference Include="Microsoft.EntityFrameworkCore" Version="3.1.1"/>
<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.1"/>

Then it worked fine

score 0 · Answer 33 · answered Nov 19 '20 at 22:49

In my case rebuilding the Project worked fine. Running the project worked fine too and executing some endpoints worked.

But still on update-database it would say "Build Failed" without any clarification, even with -Verbose added to the command.

At the end it happened that there was an error in Unit Test project that would (for some reason) cause "Build Failed" error.

Since I have multiple projects under the same Solution, I would just rebuild the Project that I am currently working on. It appears that when this error happens that it would be better to rebuild whole Solution and resolve errors...

score 0 · Answer 34 · answered Jan 28 '21 at 10:06

Only clearing Visual Studio cache helped me

Close Visual Studio (ensure devenv.exe is not present in the Task Manager)
Delete the %USERPROFILE%\AppData\Local\Microsoft\VisualStudio\16.0\ComponentModelCache directory.
Restart Visual Studio. You could also need to cleanup your user's temp folder. It is usually located under %USERPROFILE%\AppData\Local\Temp.

score 0 · Answer 35 · answered Mar 03 '21 at 16:48

0

I had the same problem. If you have opted .NET Core tool collect usage data for Windows improvement then you can use dotnet build to get the missing/persisting problem.

answered Mar 03 '21 at 16:48

utkarsh2299

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score 0 · Answer 36 · answered Apr 07 '21 at 07:50

In my case it was sonarqube dependencies that were missing. When I built the project in Rider it succeeded but failed when triggered the build (dotnet build) from terminal. This was caused by a incorrect setup in Rider. The solution was to trigger a sonar scan in terminal.

score 0 · Answer 37 · answered Jun 21 '22 at 04:53

I faced the same error. The issue in my case was that I was running my backend server with the watch build and since .Net Build was overburdened, it was unable to execute the add migration command at the same time, therefore I had to stop running the application and then run the migration command again.

score 0 · Answer 38 · answered Mar 31 '23 at 15:41

0

Also, don't forget to check in what folder you are now in the package manager (PM) console. You can use "ls" command in windows to check the list of subfolders.

answered Mar 31 '23 at 15:41

Oleksii Zhyglov

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EF Core add-migration Build Failed

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