E: Malformed line in source list_
E: Malformed line in source list
Ubuntu just hit error E: Malformed line in source list, which corresponds to a fault called "E: Malformed line in source list". This is one of the most searched error codes for this OS — you're not alone, and there's a clear fix.
What Actually Happened
Package manager encountered: a repository entry in /etc/apt/sources.list has invalid or outdated syntax.
Symptoms
APT command failed: 'E: Malformed line in source list'
Common Causes
- Package state: a repository entry in /etc/apt/sources.list has invalid or outdated syntax
How to Fix It
-
01
Refresh package index:
sudo apt update -
02
Fix broken dependencies:
sudo apt --fix-broken install -
03
Configure pending packages:
sudo dpkg --configure -a
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Root Cause Breakdown
dpkg/APT constraint resolver aborted transaction.
Should You Worry?
Safe. Package manager halts to prevent further corruption.
Power-User Tip
Always run sudo apt update before attempting repair commands.
Always free