A fatal error occurred. The folder [/usr/share/dotnet/host/fxr] does not exist

Question

I can't access dotnet after an update. Reinstalling dotnet and vscode didn't help.

On Ubuntu 22.04, running dotnet --info produces the output:

A fatal error occurred. The folder [/usr/share/dotnet/host/fxr] does not exist

Answer 1

When .NET (Core) was first released for Linux, it was not yet available in the official Ubuntu repo. So instead, many of us added the Microsoft APT repo in order to install it.

Now, the packages are part of the Ubuntu repo, and they are conflicting with the Microsoft packages. This error is a result of mixed packages.

So you need to pick which one you're going to use, and ensure they don't mix. Personally, I decided to stick with the Microsoft packages because I figured they'll be better kept up-to-date.

First, remove all existing packages to get to a clean state:

sudo apt remove dotnet*
sudo apt remove aspnetcore*
sudo apt remove netstandard*

Then, create a file in /etc/apt/preferences.d (I named mine 99microsoft-dotnet.pref, following the convention that files in such *.d directories are typically prefixed with a 2-digit number so that they sort and load in a predictable order) with the following contents:

Package: *
Pin: origin "packages.microsoft.com"
Pin-Priority: 1001

Then, the regular update & install:

sudo apt update
sudo apt install dotnet-sdk-6.0

If you would rather use the official Ubuntu packages, remove all the existing packages as above, but instead of creating the /etc/apt/preferences.d entry, just delete the Microsoft repo:

sudo rm /etc/apt/sources.list.d/microsoft-prod.list
sudo apt update
sudo apt install dotnet-sdk-6.0

However, note that the Microsoft repo contains other packages such as PowerShell, SQL Server Command-Line Tools, etc., so removing it may not be desirable.

I'm sure it's possible to make the APT config more specific to just these packages, but this is working for me for now. Hopefully Microsoft and Ubuntu work together to fix this soon.

More info on the issue and various solutions is available here:

• https://learn.microsoft.com/en-us/dotnet/core/install/linux-package-mixup
• https://github.com/dotnet/core/issues/7699

Answer 2

I had a same error and I did install .Net with microsoft packages. I think the problem is if you have had older .Net or mixing scenarios regarding Ubuntu package and .Net packages(f.x via Jammy or PMC). BTW, I solved my problem to stick with Ubuntu packages and did run this bash script :

# First, try to remove/uninstall older .Net, if any, then install .Net 6
echo "$(tput setaf 3)Installing .Net 6$(tput sgr0)"
sudo apt remove 'dotnet*'
sudo apt remove 'aspnetcore*'
sudo apt remove 'netstandard*'
sudo rm /etc/apt/sources.list.d/microsoft-prod.list
sudo rm /etc/apt/sources.list.d/microsoft-prod.list.save
sudo apt update
sudo apt install dotnet6

Answer 3

I've got this error message after:

sudo apt install dotnet-host

This solved it for me:

sudo apt install dotnet-sdk-6.0

Answer 4

1. First of all, you need to run using super user

sudo su

insert you password and go to seccond point:

2. If you only want to run a .net code

install dotnet-host-7.0

2.1) If you want to develope systems using .net

apt install dotnet-sdk-7.0

---

If you want to remove olders versions:

sudo apt remove 'dotnet*'
sudo apt remove 'aspnetcore*'
sudo apt remove 'netstandard*'

Answer 5

In case anyone encounters the same error right now (2023 July), I've tried a lot of the comments and blog posts, but this worked for me perfectly:

There is a part:

dotnet --version
A fatal error occurred. The folder [/usr/share/dotnet/host/fxr] does not exist
Great.

Since there, just follow along and it works :)

Not my solution, all respect to the author of this post:

https://alexanderzeitler.com/articles/fixing-my-bricked-dotnet-sdk-6-installation-on-xubuntu-ubuntu-after-dotnet-7-sdk-installation/

Answer 6

In my case I had to remove /etc/apt/sources.list.d/mssql-release.list which had been installed as part of some other work where I needed ODBC drivers. It says mssql, but that's the same source as the MS dotnet packages, causing the interference.

To stick with just the Ubuntu packages:

sudo rm -f /etc/apt/sources.list.d/mssql-release.list
sudo apt purge dotnet* aspnetcore* netstandard*
sudo apt update
sudo apt install dotnet-sdk-6.0

Answer 7

I had this error when I created a new VS Code Dev Container using Ubuntu Jammy and selecting the "dotnet CLI" feature. I ended up switching my Dev Container to use Focal and the problem went away.