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I have a solution which uses Solution Folders to split out the projects. In the Visual Studio IDE, the solution builds fine.

However when running the build using MSBuild from the command line, I get the following error:-

Solution file error MSB5023: Error parsing the nested project section in solution file. A project with the GUID "{Some Project GUID}" is listed as being nested under project "{Some Solution Folder Project GUID}", but does not exist in the solution.

Now I've checked these two GUIDs over, and they exist, one as a project, the other as the solution folder that the project is nested under. There shouldn't be any problem.

Does anyone have a way to resolve this?

Liam
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Sean Holmesby
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  • Note a dupe, but has very similar fixes to the problem: https://stackoverflow.com/questions/6599966/team-foundation-server-2010-msbuild-error-parsing-the-nested-project-section – StayOnTarget May 17 '19 at 14:12

7 Answers7

90

I faced the same issue and managed to sort out:

  1. Opened .sln in NotePad and found Guids
  2. One of my projects wasn't closed ("EndProject" was missed)

Cheers, hope this can help anyone

Denis Evseev
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    This was the solution for me. After a git conflict I had a malformed sln file lacking an `EndProject` line – gvdm Dec 12 '18 at 23:18
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    I had this problem after resolving a git conflict. I found concatenation of "EndProjectProject" in .sln and just added the break line to split it. – Artem Kolokoltsev Jul 14 '21 at 14:27
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    While my issue wasn't a closing EndProject tag, this helped! Turned out my solution was trying to add a ProjectSection that no longer existed. I moved the ProjectSection and that resolved my issue. – bluefox Jan 31 '23 at 19:19
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Or you can add a new file to the solution and save. This should rebuild the solution. After confirming the build is working fine, the file can be safely removed and saved.

Pon Saravanan
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    I added a solution item and saved the solution. I'm not sure the same thing will happen if you add a file to a project instead. – Daniel Gabriel Dec 06 '18 at 17:40
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    It created a "Solution Items" folder when I did this (which I later removed). This procedure corrected the error, which turned out to be a missing "EndProject" line. – StayOnTarget May 17 '19 at 14:10
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    For me this also helped. The problem wasn't with the missing `EndProject` tho, there was a leftover guid that should have been removed from .sln – Mr. Blond Apr 20 '20 at 14:21
  • Ohh this is briliant thank you. |Git merge messed up my sln I had no clue what to do.. just did what you said.. added a project. save.. boom fixed it up (stoopid thing is in vs it build in dotnet cli it didnt) doh – Piotr Kula Jun 15 '22 at 16:12
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It's probably answered already but I'd mention in steps to make it even easier to do.

Steps to fix:

  1. Add a new dummy project to the solution
  2. Use Save All button to update the solution
  3. Remove the dummy project added earlier & build. And it's fixed
  4. Additionally if you are using source control, compare the updated .sln file with old one to know the missing changes.
Dash
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4

It is possible you may also have an issue where the line could have gotten in here with a merge conflict where it wasn't deleted when a project was deleted. If you can't find any other references in your project with a global search of the GUID, try deleting the line in the .sln file and rebuilding.

daniel.caspers
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1

Due to a merge conflict, my solution file was trying to stick two projects in a solution folder that didn't exist anymore. the NestedProjects section near the bottom mentioned a Guid that was removed from the Project enumeration at the top.

increddibelly
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There is a possibility that it is a merge conflict problem that changed the .sln file, confirm that it is not the case by opening in your favorite text editor and checking if there is any conflict markup.

Guilherme Jannotti Arantes
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I created a blank solution and add my csproj. After this, my YAML in Azure DevOps can build the application

Felipe Augusto
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