Fix "Permission Denied" in Linux

Check file permissions

Start by inspecting the file's permissions:

ls -la filename

The output looks like -rw-r--r--. The first three characters after the dash are the owner's permissions: r (read), w (write), x (execute). If you're trying to run a script and the x bit is missing, add it:

chmod +x script.sh

For a file you just need to read, ensure read access is set:

chmod 644 file

This gives the owner read/write and everyone else read-only.

Check file ownership

Even with correct permissions, you can be denied access if you're not the file's owner and not in its group. Check with:

ls -la filename

The third and fourth columns show the owner and group. If the file is owned by another user, change ownership:

sudo chown youruser:yourgroup filename

For an entire directory and its contents, add the -R flag:

sudo chown -R youruser:yourgroup directory/

Use sudo when required

Some operations require root privileges—editing system configuration files, installing packages, or managing services. Prefix the command with sudo:

sudo command

However, don't reach for sudo as a default fix. It's a privilege escalation. If a file in your home directory requires sudo to access, the real problem is usually wrong ownership (see Step 2). Only use sudo when the operation genuinely requires root.