hi, I'm totally new to linux.

running linux mint sonya


when trying to open synaptic i ran into an error regarding 'sudo'


E: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/mono-official.list
E: The list of sources could not be read.
Go to the repository dialog to correct the problem.
E: _cache->open() failed, please report.


tried getting update and unable running into same error in terminal.

tried searching for issue and found several similar issues but none exactly like mine and most regarding 'mono-xamarin.list'

i am not sure how to fix this. can anyone help me? i am super new and still not sure how to even use the terminal or anything.

thanks for your help and patience with me.

That would seem to indicate that you have 'sudo' on the first line of your sources.list and I don't know why you would have that.

What was the exact command you entered?

Welcome to LQ!!!
Can you post at least the first line of that file (since it complains about it)
Also maybe file timestamps, as a clue to when the 'badness' happened
(stat or ls with switches; see man; also the .d but ls needs -da for that)
There's GUI ways to see dates, but Idk GUI (like you don't CLI)

Is this a new install? (Reinstall?)
Ever done anything 'awful' like: sudo echo sudo >ThatFile?

I realize you probably just click on the GUI to run it; you probably tried cli: apt update
Since you've done good web-searching, look for ways to: clean 'bad repositories'
https://askubuntu.com/questions/9696...ce-list-update
(My ISP's login page once got dumped into something like this!!!)

Have patience&persistence!!! The hundreds of LQ volunteers will 'get you thru this'

I first ran into the issue when trying to open Synaptic. After entering my pswd and synaptic opens, I am immediately given an error box with

E: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/mono-official.list
E: The list of sources could not be read.
Go to the repository dialog to correct the problem.
E: _cache->open() failed, please report.


Then, I opened terminal and tried:

sudo apt-get update




To which I received:

E: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/mono-official.list
E: The list of sources could not be read.

LOL I am so new to Linux, I honestly didn't understand some of that.


I first ran into the issue when trying to open Synaptic. After entering my pswd and synaptic opens, I am immediately given an error box with

E: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/mono-official.list
E: The list of sources could not be read.
Go to the repository dialog to correct the problem.
E: _cache->open() failed, please report.


Then, I opened terminal and tried:

sudo apt-get update




To which I received:

E: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/mono-official.list
E: The list of sources could not be read.



I then tried 'man' and 'stat' but I don't think I did it right. Just entered 'man' and then tried 'stat'.

I then tried cli: apt update and was returned:


cli: apt update
No command 'cli:' found, did you mean:
Command 'clit' from package 'convlit' (universe)
Command 'cli' from package 'mono-runtime' (main)
Command 'clip' from package 'geomview' (universe)
Command 'clif' from package 'clif' (universe)
cli:: command not found



I don't know what GUI is or how to use it. I'm sorry, I am so new to this. I did try to search up how to fix bad repositories and it seemed to turn up fixes that involved using 'sudo' commands

breaking it down:
/etc/apt/sources.list.d/mono-official.list is a file on your system.
it contains invalid syntax, namely the string 'sudo'.
it doesn't take a linux genius to immediately see that someone or something entered a whole command into a file that should only contain links to repositories.
please, issue the following command:and post the output, including the command itself, here.

bonus points if you put it in code tags.

edit (off topic):
i mildly chuckled: