You run ng serve --port 4200 but get an error that the port is already in use. What is the best way to fix this?

medium📝 Debug Q6 of 15

Angular - Fundamentals

You run ng serve --port 4200 but get an error that the port is already in use. What is the best way to fix this?

ARestart your computer to free the port

BDelete node_modules folder and reinstall

CRun <code>ng serve --port 4200</code> again immediately

DRun <code>ng serve --port 0</code> to let Angular pick a free port automatically

Step-by-Step Solution

Solution:

Step 1: Understand port conflict error
If port 4200 is busy, Angular CLI can pick a free port if you specify port 0.
Step 2: Use port 0 to auto-select free port
Running ng serve --port 0 lets Angular find an available port automatically.
Final Answer:
Run ng serve --port 0 to let Angular pick a free port automatically -> Option D
Quick Check:
Port 0 means auto-select free port [OK]

Quick Trick: Use port 0 to auto-select free port if busy [OK]

Common Mistakes:

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