You need to edit your question to include which build of Windows 10 you are using. The solution to your problem will be determined by which build you are using.

Just added the OS build and version number. Thank you.

By chance were you using WSL, when you had 1703, installed? Because your method of launching Ubuntu WSL seems outdated. Did this WSL instance recently stop working?

@Ramhound: I didn't have version 1703 installed. It is the domain based machine. I got it installed with version 1709. So, I can not tell you that WSL instance stopped working. Any clue what's happening with version 1709?

Do you have the OpenSSH Beta Windows Feature enabled by chance? The error you received is a permission error. I suggest you reset the instance (by removing it and installing it again) to solve the problem. If that solves your problem I will find the duplicate which I answered with the appropriate instructions.

To have bash/Linux like environment, I tried to activate Developer mode. It turned on but with error 0x800f0954. Then, the above errors I described in my question. I don't know if this errors are related. I mentioned before my machine is on network domain so it might lack some IT permissions. What do you think?

Developer mode isn't required for Windows Subsystem for Linux since you are running 1709. Which is the reason I asked if you had ran 1703 or an earlier version of Windows 10 where it was required. Your question makes no mention of the fact you are connected to a Active Directory domain.

My bad. I just edited my question. I don't think so I had any previous version installed. It switched from Windows 7 to 10 and it was a fresh w10 installation.

You performed the switch or somebody performed for you?

0x800f0954 is indeed associated with your non-Administrator status which does not matter, since Developer Mode, isn't required to enable Windows Subsystem for Linux since you are running 1709.

Is this by chance a Enterprise version of Windows 10?

The IT department did it for me. I think it's Windows 10 education.

You also failed to mention that fact. Have you confirmed, from the IT department, that you should be able to use WSL?

No. I haven't confirmed

Do you suggest to do that first?

Yes

But why are you running the WSL Ubuntu instance as an Administrator anyways?

That shouldn't be required

Alright. Will do. What if it is not allowed?

If it's not allowed you cannot run WSL on your machine

But I can also not run bash on Windows cmd

That's the main issue

You wouldn't be able to if the instance isn't installed correctly

But I installed some packaged inside Ubuntu app

Like r software

Which is the reason I suggested you reset the instance. However, if you cannot run a command prompt and/or a PowerShell anyways, then that is the source, of the permission error you have received

Bash is the old method of running WSL which is only applicable. on earlier versions of Windows 10

I will try and come back to you

Thanks

You want to launch ubuntu.exe instead of bash.exe

specifically ubuntu.exe /run from a command prompt provided you want it to work like bash.exe did otherwise just launch the Ubuntu instance like you already did

Why are you launching Ubuntu as an administrator if you don't have Administrator permissions?

I can't answer your first part of your question without that bit of information