Fix Roblox Error Code 279: ID Connection Failed (2025)

Updated: 11/29/2025

You click 'Play', the green loading screen appears, and just as you think you are in, it drops you with: 'Failed to connect to the Game. (ID=17: Connection attempt failed). Error Code: 279'. This error is a network handshake failure. It means your computer tried to connect to the Roblox game server, but something blocked the returning data packet—usually a Firewall, an AdBlocker, or a slow internet response.

Method 1: Allow Roblox Through Firewall

Windows Firewall often treats the Roblox game engine as a suspicious background process.

Step 1: Open Firewall

Press the Windows Key and type 'Allow an app through Windows Firewall'.

Step 2: Change Settings

Click the Change settings button at the top right.

Step 3: Check Roblox

Scroll down to find Roblox. Ensure BOTH the 'Private' and 'Public' boxes are checked. Click OK and try playing.

Method 2: Disable Browser Extensions

If you launch games from the website, aggressive ad-blockers can break the launch script.

Disable AdBlock Plus, uBlock Origin, or any 'Roblox Theme' extensions. These sometimes block the port required for the game client to talk to the website authentication server.

Method 3: Port Forwarding (Advanced)

If you are on a strict network (School/Work), the specific Roblox ports might be closed.

Log into your router and open the following UDP ports for your PC's IP address:

UDP Range: 49152 - 65535
Note: This is rarely needed for home connections, but essential for restricted dorm/office networks.