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I recently migrated a VSS database to TFS 2008. Using Source Control Explorer, I got the latest version of a solution with 12 projects.

When I opened the solution in VS 2005, two of the projects were not found. I am not sure why these two projects were not found, but thought it easiest to just delete and re-add them to the solution.

When I do this, VS gives me a "A project with that name is already open in the solution." The project doesn't appear in solution explorer, and is not listed in the .sln file.

Any ideas?

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  • 4
    You may need to run VS as Administrator if IIS is involved.
    – Paul Matovich
    Commented Feb 14, 2023 at 22:53
  • VS as Admin was the fix for me. I had the project configured to use Local IIS as the hosting platform and did not start VS as admin
    – Stuart
    Commented Apr 3 at 10:42

25 Answers 25

Reset to default
91

I had the same message... Seems like it comes from (.csproj) project file. Under first propertygroup there is a section named

<ProjectTypeGuids>...</ProjectTypeGuids>

which generally tells Visual Studio to handle that project in some specific way. Some Guids can be found here.

First make a backup copy of that file. Then removing that section can help you open the project as usual project. As it seems that the Visual Studio thinks that the project is not the type that is specified in the ProjectTypeGuids.

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  • 1
    Tnx, you have just saved my day:)
    – deanpodgornik
    Commented Jul 14, 2014 at 9:02
  • 12
    Worked for me BUT note that you need to close VS and reopen.
    – Gary Huckabone
    Commented Feb 16, 2017 at 21:32
  • 1
    Worked for me in VS 2022 Community Edition. I restarted Visual Studio after editing the csproj file and the unloaded project was now loaded normally.
    – user2444499
    Commented Aug 15, 2022 at 23:26
  • 2
    This is the only thing that worked for me (opening a .NET Framework 4.8 solution in Visual Studio 2022 Ultimate for the first time)
    – Dan Cook
    Commented Aug 31, 2022 at 4:28
  • 4
    13 years later and this answer is still valid. Thanks!
    – Don Shrout
    Commented Oct 4, 2022 at 18:20
88

I had this problem and I was able to solve it using the following steps:

  1. Remove the project from the solution.
  2. restart visual studio.
  3. add the project to the solution as an existing project.
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6
  • work for me too. but need to restart VS before step 3!!
    – Omid.Hanjani
    Commented Jul 14, 2015 at 14:00
  • 1
    its worked, Thanks :) But can anybody share the reason for such a behaviour.
    – LifeOfPi
    Commented Jan 26, 2016 at 4:53
  • 8
    Do not skip step 2 - it's essential. Maybe it's for cleansing the bad aura. Also, do not forget to add reference to the remove-and-add-back project. Or your main project won't compile.
    – Lionet Chen
    Commented Jul 22, 2016 at 1:40
  • The accepted answer did not work for me, but this solution worked. I had this issue with my Winforms VS2015 project. The reason for my comment is that not only older versions of Visual Studio can have this problem, but new ones too and the solution is the same.
    – Sarah Weinberger
    Commented Nov 11, 2016 at 21:32
  • 1
    Simple oversight on my part, but I also had to make sure I was running as Admin as well. Before that, this did not work.
    – Bonez024
    Commented Nov 4, 2022 at 13:51
68

Before anyone tries tempering with their solution- and project files, figure if you may have project dependencies outside the solution, such as IIS - and you forgot to start Visual Studio in Administrator-mode

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  • 4
    This was the problem #1 for me; and the second problem was that the IIS section was configured to use https, and I didn't have the default web site configured for https - just changing it to http fixed it.
    – Mr. TA
    Commented Jan 18, 2023 at 20:45
  • This solved it for me. Oddly, I only had this problem in 1 out of 6 projects in the same solution. The other 5 loaded well. Thank you
    – PDoria
    Commented Mar 31, 2023 at 11:57
  • 2
    Thanks! This is the only that worked for me specifically running VS on admin mode.
    – JohnnyQ
    Commented May 10, 2023 at 1:38
  • Fixed for me also. Check the output window shows the following message: "The Web Application Project <project> is configured to use IIS. You do not have permission to access the IIS configuration file. Opening and creating web sites on IIS requires running Visual Studio under an Administrator account" Why the dialog shown doesn't just say this I have no idea :shrug:
    – toepoke.co.uk
    Commented Jun 6, 2023 at 15:13
  • To add to this answer, I also had to update my .csprog from <UseIIS>True</UseIIS> to <UseIIS>False</UseIIS> because administrator-mode Visual Studio could not start the site in IIS for some reason and that was blocking the project from loading successfully. Which was fine, because I wanted to use IIS Express.
    – DavGarcia
    Commented Apr 24 at 13:07
25

For me, the project not loaded was because it was configured to use IIS on the local machine and I needed to start Visual Studio as an Administrator.

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  • 2
    This was exactly my issue too! Running VS in admin mode solved the problem.
    – Lemraj
    Commented Jan 12, 2023 at 19:43
  • Same here and I picked up on it because there was another error in the output window "The Web Application Project Web is configured to use IIS. You do not have permission to access the IIS configuration file." but that wasn't the error that popped up in the error message.
    – Paul Matovich
    Commented Feb 14, 2023 at 22:51
22

This did it for me:

  1. remove the section <ProjectTypeGuids>...</ProjectTypeGuids> in each project
  2. reopen each project, then save to overwrite the existing project file, finally exit
  3. reopen the solution file
  4. pray (optional)
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  • 15
    I don't think 4. is optional when dealing with those issues.
    – nicolas
    Commented Mar 6, 2013 at 14:08
  • #4 made my day.
    – Vishav Premlall
    Commented Jun 10, 2022 at 11:59
  • #4 is a must. If not performed, forget about the first 3 steps.
    – I try so hard but I cry harder
    Commented Nov 14, 2022 at 11:00
  • I opened the folder with VS Code, searched all files for <ProjectTypeGuids>. Removed that node from every project, saved, closed the solution, reopened the solution. Solved. Thank you for your contribution! FWIW I skipped step 4.
    – Don Rolling
    Commented Jan 12, 2023 at 17:05
  • For me, absolute pray was on optional. Thank you, it gave the solution.
    – Jeeva J
    Commented Apr 3, 2023 at 6:23
11

If anyone uses AnkhSVN instead of TFS, it's also possible, that the .sln-file need the following lines: 

GlobalSection(SubversionScc) = preSolution
    Svn-Managed = True
    Manager = AnkhSVN - Subversion Support for Visual Studio
EndGlobalSection

in the "Global" section.

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10

Unfortunately I don't know the why behind the obtuse error message, I can merely provide what steps I took to get it to go away.

In my case, I had reconfigured my local IIS (<UseIIS> not <UseIISExpress>) and it was no longer hosting the URL that was in the csproj <IISUrl> field.

Editing the .csproj file in another editor and changing that field to the new URL, followed by closing and opening the solution in VS resolved the issue.

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2
  • This solved it for me. There was a clue in the output when opening the solution "error : The Web Application Project {ProjectName} is configured to use IIS. The Web server 'localhost:{portNumber}/' could not be found."
    – Dizzy
    Commented Dec 9, 2022 at 10:03
  • For me, the issue was the IIS section was configured to use https, and I didn't have the default web site configured for https - just changing it to http fixed it. (This after starting VS as administrator.)
    – Mr. TA
    Commented Jan 18, 2023 at 20:44
7

Delete .suo file. Build solution. Add Projects.

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0
6

I have to say that removing the section <ProjectTypeGuids>...</ProjectTypeGuids> could create some problems. In fact, such a section defines the type of the project and, if removed, could disable some features. For example, if your project was originally defined as Smart Device (C#), after removing the aforementioned section the on-device debug may not working properly.

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4

Somehow VS 2022 doesn't create a virtual directory anymore. I had to manually create the website in IIS

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4

I got it in Visual Studio 2022 version 17.4.4. You may also see:

Error HRESULT E_FAIL has been returned from a call to a COM component.

when you try to reload your project.

One way to load the project (and deal with IIS directories later) is to edit the .csproj file and set UseIISExpress to true. Replace:

 <UseIISExpress>false</UseIISExpress>

with

 <UseIISExpress>true</UseIISExpress>

Then you need to close your solution and open it again and the project should load.

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1
  • This one may solve the issue locally but while integrating testing it would create problem when you have different portal integration.
    – Shashank
    Commented Jun 5 at 18:08
2

I would try hand editing the project/solution files, they are text and pretty easy to read. You can edit the file in notepad. To open up the file as text in visual studio you need to first close the solution. Then do file->open and select the sln file, but instead of hitting the open button, press on the right side where there is an arrow and select open with.. from there you can select source code editor (text).

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1

I had the same problem when i migrated a website to a web app project.

  1. Unload the web app.
  2. Add the existing website.
  3. Reload the web app.
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1

The following worked for me when I moved a project running vs2010 to another laptop.

I removed exactly the following and it worked:

<ProjecctType>Guid of sorts</ProjectType>
<SccProjectName>Svn</SccProjectName>
<SccLocalPath>Svn</SccLocalPath>
<SccAuxPath>Svn</SccAuxPath>
<SccProvider>SubversionScc</SccProvider>
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  • 1
    it worked for me, thanks - i just needed to close the solution and restart VS2005 in order for it to work after the edit.
    – eladyanai
    Commented Jul 7, 2013 at 8:11
1

For those looking for this while dealing with VSTO projects...

Be sure to have the Office Tools for Visual Studio installed in your machine before opening the project.

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  • I (also?) had to install "Microsoft Visual Studio Tools for Applications" (it appeared to be for vsta at first but now VS wants to open the project)
    – franckspike
    Commented Jun 16, 2016 at 18:12
1

I solved it by changing Windows' regional settings. Instead of "English (Europe)", I used "English (United States)". Others have reported similar behaviors with changing for example from "Russian (Ukraine)" to "Russian (Russia)", etc. -AlessandroSegala

Work For me.

Ref: http://answers.microsoft.com/en-us/windows/forum/windows_10-windows_install/customized-cultures-cannot-be-passed-by-lcid-only/26eb9d4b-7ddb-4774-8a40-7a7d84ba9277?auth=1&rtAction=1455534187354

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1

In my case it was corrupted vbproj file. First line was missing:

<?xml version="1.0" encoding="utf-8"?>

After adding this line I had to close the solution, delete .vs folder and open again.

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1

I encountered this issue with web application projects. When I tried to reload the projects, the VS2022 output said something like :

"The project is configured to use IIS. Unable to find the server '{site_url}' on the local computer. Ensure that the local IIS is configured to handle secure communications."

Which is pretty clear. Indeed, in my case, this was caused by my website https binding that just vanished for no reason (it happened to me several times, looks like a bug with Windows 11 & IIS 10). Things got fixed when I got my https binding back (projects could load normally).

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1

I had the same issue in a .NET Framework project. I was using VS2022.

Before trying this please keep backup of the files you are editing.

Still unaware why this happened suddenly. But the following worked for me.

  1. Remove the project from the solution list in visual studio
  2. Go to the solution (.sln) file and open it in an editor
  3. Remove the entries that you have for your project which can't be loaded.

Example : Remove the following that is right before GlobalSection :

        Project("{FCA04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Web", "Web\Web.csproj", "{5CA8CA45-47D0-4AC8-9BDF-2030B751CC10}"
EndProject

Also remove the followings from the GlobalSection :

        {5CA8CA45-47D0-4AC8-9BDF-2030B751CC10}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
        {5CA8CA45-47D0-4AC8-9BDF-2030B751CC10}.Debug|Any CPU.Build.0 = Debug|Any CPU
        {5CA8CA45-47D0-4AC8-9BDF-2030B751CC10}.Release|Any CPU.ActiveCfg = Release|Any CPU
        {5CA8CA45-47D0-4AC8-9BDF-2030B751CC10}.Release|Any CPU.Build.0 = Release|Any CPU
  1. Close Visual Studio.
  2. Open Visual Studio in administrator mode.
  3. Add existing project.

It should work now.

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0

In VS 2022 to open a legacy web project I had to:

  1. Remove from Solution
  2. Change framework version from 4.6.x to <TargetFrameworkVersion>v4.7.2</TargetFrameworkVersion> in from csproj
  3. Remove <OutputType>Library</OutputType> from csproj
  4. Close Solution and open it again (!!!)
  5. Add project to the sln again.
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0

I had this problem too. I am sure that some of these solutions work for some people's circumstance, however, none of the solutions worked for my situation (which is more recent than this 14 year old problem). In my situation, I had recently gone through a rebuild of my PC. A project that once loaded on my older machine, no longer loaded under the new build. It turned out, I hadn't yet created the IIS applications (and appropriate folders) for those projects. The clue in my case was that only web application projects were not loading. So get those folders setup in your inetpub/wwwroot/#application# and it might start behaving once again. After setting up the folders, you may need to restart your IIS session.

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Basically you need to exit visual studio and start again as administrator, it should work.

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In VS2022

  1. Close VS.
  2. Delete (or backup) the hidden .vs folder.
  3. Open VS and solution.
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0

What I understood, it is very generic message and underlying error could be anything.

In my case I did two changes.

  1. IIS configuration of the project was not correct also website having more binding than expected. I deleted all bindings and left only http and https
  2. Uncheck option, Tools -> Options- > Project and Solutions -> Allow Parallel project initialization.

After those correction I had restarted the VS and loaded the application again.

--- Updated --- This error message appeared again, this time somehow I was missing port 80 for my website in IIS. To fix this issue I had added http/80 in website Binding and it fixed my issue.

As I said earlier, this is generic error it could be any other underlying issue.

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0

If it's possible, you can use an older version of VS.

Nothing worked for me, but I still had VS 2019 installed, that worked without issue.

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