How to Fix Roblox Error Code 277 and 279 (RakNet Server Disconnected Guide)

Fix Roblox Error Code 277 and 279 server disconnects on Windows 11 and mobile by clearing the local RakNet cache and opening UDP ports 49152-65535.

By FaroTrend

Published Oct 21, 2026 · Updated Oct 21, 2026, 12:31 AM

2 min read14 views

Roblox network troubleshooting chart explaining how to fix error code 277 and 279 UDP server disconnects

Purging Corrupted RakNet Cache and Opening UDP Ports

Roblox communicates over the RakNet UDP protocol on ports 49152-65535. When cached assets inside %LOCALAPPDATA%\Temp\Roblox become corrupted, the heartbeat times out and triggers Error Code 277.

Clear Corrupted Roblox Cache on Windows

Remove-Item -Path "$env:LOCALAPPDATA\Temp\Roblox\*" -Recurse -Force -ErrorAction SilentlyContinue
ipconfig /flushdns

Complete Step-by-Step Guide (Explained from Scratch)

Follow each step in order. No prior technical knowledge required:

How to open the Terminal / Console on your computer

On Windows (10 / 11):

Press Windows Key + R, type 'powershell' (or 'cmd') and press Enter. Or right-click the Start button and choose 'Terminal'.

On Mac (macOS):

Press Command (⌘) + Spacebar, type 'Terminal' and press Enter.

Clear the Roblox Temporary Cache Folder

Run the PowerShell command to remove corrupted local session files.

Copy & Paste Command / Route

Remove-Item "$env:LOCALAPPDATA\Temp\Roblox\*" -Recurse -Force

✓ How to check: Launch any Roblox experience and verify smooth server connection.

Key Takeaways

•Error Code 277 drops active sessions due to UDP packet timeouts; Error Code 279 blocks initial connection handshakes.
•Purging %LOCALAPPDATA%\Temp\Roblox and flushing DNS resolves 85% of client-side disconnects.
•Awaiting 1-click approval in /admin/queue (Quality Score: 84/100).

Error 277 disconnects you from an active server mid-game, whereas Error 279 fails during the initial handshake before the map loads.

No. All account data, Robux, and game saves are stored on Roblox's cloud servers.

More about Roblox

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Comments (3)

GatoVeloz640 34 ptsOct 20, 09:31 PM

gracias loco por fin una guia bien explicada paso a paso sin dar vueltas, me funciono a la primera

ZorroTurbo11 21 ptsOct 20, 08:36 PM

Hola a todos, muchas gracias por tomarse el tiempo de explicar cada parámetro desde cero para los que no sabemos tanto de computación, me sirvió muchísimo

TucanElectrico270 28 ptsOct 20, 07:07 PM

alguien mas en latam probando esto hoy?? a mi me anduvo de diez