The IIS Express applicationHost.config file contains invalid entries and must be corrected before you can open project

Question

I have installed Visual studio developer community version to practice coding. When I tried to create a new web project, I am facing issue like configuring IIS express failed, can not read the configuration file. I have tried all possible solutions like renaming the host file and closing and opening the visual studio. Nothing worked out. And I have tried to clone the project from git here also I am facing the same issue. Can someone please help me here.

Here is my error message.

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try the solutions mentioned in this post [here](https://stackoverflow.com/a/25429425/3377344). — psj01, Jan 12 '20 at 06:36
This may help you https://stackoverflow.com/questions/24582929/unable-to-create-a-new-web-project-in-visual-studio-2013 — Seyedraouf Modarresi, Jan 12 '20 at 06:43

score 70 · Answer 1 · answered Jul 12 '20 at 05:52

70

Go: C:\Program Files (x86)\IIS Express\config\templates\PersonalWebServer
Copy 3 files: applicationhost.config, aspnet.config và redirection.config
Go to: Documents\IISExpress\config
Paste and replace all 3 files
Reload

answered Jul 12 '20 at 05:52

Drave

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Don't know what's the cause of error, but it did solve it :D – Usama Saleem Jun 15 '21 at 10:50
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Onedrive had synced my `Documents\IISExpress\config` files from another computer which could have been the culprit. – h-rai Jul 22 '21 at 23:48
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Had same issue, but just because I have 2 versions of visual studio installed. – N.K Nov 15 '21 at 07:22
On a 64-bit setup, you may need to get the files from C:\Program Files instead of C:\Program Files (x86). – Tom McAnnally Dec 20 '22 at 21:18
I found that the files are not there, just one drive equivalent of these files – Rikudou En Sof Feb 22 '23 at 04:28
You sir are the people's champion. I'm wondering if installing build tools causes this somehow. I'm working with a fresh machine so this is quite odd. – KingOfHypocrites Apr 24 '23 at 20:41
This works, in my case because OneDrive replaced my new files – André Ibarra Jun 16 '23 at 16:45

score 2 · Answer 2 · answered Dec 05 '20 at 19:16

2

I solved the problem with help of Drave answer. But I put that 3 files into below address:

[my project]\.vs\config\

when I put that files into confing folder and I reloaded the project, problem solved.

tnx again from Drave answer

answered Dec 05 '20 at 19:16

Hamed Rezaei

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score 2 · Answer 3 · answered Sep 06 '22 at 03:53

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Here is another suggestion which seems a bit easier.

Navigate to C:\Users\{{your user name}}\Documents\
Rename the folder IISExpress to IISExpressold or something so that its archived
Open your solution again.

It should open ok after these steps.

answered Sep 06 '22 at 03:53

Jon Cianci

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score 1 · Answer 4 · answered Sep 27 '22 at 17:44

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In my case with VS2019 works:

close VS2019
remove [my project].vs\config\
rename c:\Users[username]\OneDrive\Documents\IISExpress\config to _config
rename c:\Users[username]\Documents\IISExpress\config\ to _config
load the solution to VS2019

answered Sep 27 '22 at 17:44

Elina Sitaylo

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score 0 · Answer 5 · answered Aug 25 '21 at 13:05

In my case, the OneDrive application is removing by default the content of "C:\Users\username\Documents\IISExpress\config" folder, so Visual Studio cannot copy the .config files into .vs folder on the solution directory.

I resolved it by ensuring the files are on this path, and disabled the backup option on Documents directory in the OneDrive settings.

score 0 · Answer 6 · answered Apr 15 '23 at 10:47

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As suggested by @silas my issue was with OneDrive as well. after disabling OneDrive sync on "Documents Folder" problem gets resolved. To be precise system was trying to access "C:\Users[user name]\Documents\IISExpress\config"

answered Apr 15 '23 at 10:47

Kashif Atiq

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The IIS Express applicationHost.config file contains invalid entries and must be corrected before you can open project

6 Answers6