how to fix permission denied in terminal linux

groups

If not, you need to add the user:

usermod -aG sudo yourusername

Log out and back in for changes to apply.

Check File Ownership

Maybe the file or directory isn’t owned by your user.

ls -l filename

To change the owner:

sudo chown yourusername:yourusername filename

This is especially useful if you’ve downloaded files or copied them from another user account.

SELinux or AppArmor Might Be Blocking Access

Some Linux distributions use security modules like SELinux or AppArmor which may silently block execution or access.

For SELinux (check status):

sestatus

Temporarily disable it for debugging (not recommended for production):

sudo setenforce 0

Or check audit logs:

sudo ausearch -m avc -ts recent

If you’re on Ubuntu and AppArmor is active, check profiles:

sudo aa-status

Check Mount Options

If you’re running a script from a mounted partition (like /media or an NFS share), check if it’s mounted with noexec option.

mount | grep yourmountpoint

If you see noexec, remount it:

sudo mount -o remount,exec /mount/point

Hidden Characters or CRLF from Windows

Files edited in Windows might carry hidden carriage return characters (^M) that cause permission errors.

Check with:

cat -A script.sh

To fix:

dos2unix script.sh

If you don’t have dos2unix, install it via your package manager:

sudo apt install dos2unix

Executing a Directory Instead of a File

This might sound simple, but running a directory instead of a file gives the same error.

Double-check with:

file your_target

If it says “directory”, that’s your problem.

Wrong Shell in Script Shebang

If the shebang (#!) in your script points to a non-existent shell, the script won’t execute.

Open the file and check the first line:

#!/bin/bash

which bash