How to Fix Roblox Error 272 (Disconnected / Security Key Mismatch)

By FixMyError · Updated October 16, 2026 · 8 min read

What error 272 means

When you join a game, Roblox runs a security handshake between your client and its servers — a quick check that the copy of Roblox on your machine is the genuine, unmodified one. Error 272 means that handshake failed: the server decided your client does not match the expected "security key," so it pulled you out of the game. In most cases this happens because the security system detected exploit or cheat software running alongside Roblox, or leftover files from tools like script executors.

It is important to understand that this is not a connection error like 277 or 279. Flushing your DNS or restarting your router will not help, because your internet is not the problem. The game is deliberately refusing to trust your client. If you genuinely never installed anything shady, do not panic — false positives are real. Certain browser extensions, macro programs, modding leftovers, or aggressive antivirus software can all trip the same detector. Either way, the path back into the game is the same: get the flagged software off your machine, clean the client, and start fresh.

Common causes

• Exploit or cheat tools running on your PC: the classic cause. Script executors, cheat engines, and "mod menu" programs are exactly what the security key check is designed to catch. Even having them open in the background without using them can trigger error 272.
• Leftover files from removed cheat tools: uninstalling a tool incompletely leaves behind DLLs, folders, and registry entries that Roblox still scans. Simply closing the program is never enough — it has to be gone from the machine entirely.
• Browser extensions Roblox mistakes for injectors: extensions like Tampermonkey, RoPro, or BTRoblox interact with Roblox pages and scripts, and the security system can read them as cheating-adjacent software.
• Corrupted or tampered Roblox client files: if a crash, a bad update, or another program modified your Roblox installation, the security handshake fails even though you did nothing wrong. This is the "false positive" case for most honest players.
• Security software interfering with the client: antivirus programs and firewalls that hook into game processes can alter how the client behaves at runtime, which looks like tampering from the server's point of view.

How to fix error 272 — step by step

Work through these in order. The first two steps solve the problem for the vast majority of players; the later ones handle false positives and stubborn leftovers.

1. Remove every exploit or cheat tool completely. On Windows, open Settings, then Apps, then Installed apps, and uninstall any exploit, script executor, cheat engine, or mod tool — completely, not just by deleting the shortcut. Check your Documents and Downloads folders for leftover tool folders and delete those too. Roblox keeps flagging these while they remain installed, so half-measures do not work.
2. Restart clean with no background helpers running. Restart your PC. Before opening Roblox, press Ctrl + Shift + Esc to open Task Manager and end anything suspicious still running — game modders, script injectors, macro tools, "FPS booster" apps with script injection. Then launch Roblox with a clean background. If the error disappears, one of those programs was the culprit.
3. Strip out Roblox-related browser extensions. In Chrome or Edge, go to the extensions page (type chrome://extensions or edge://extensions in the address bar) and remove Tampermonkey, RoPro, BTRoblox, and any other extension tied to Roblox or scripting. Restart the browser afterward. These extensions are the most common cause of false-positive 272 errors.
4. Delete the Roblox cache and temporary files. Close Roblox completely, then press Win + R, type %localappdata%\Roblox, and delete the logs and downloads folders. This clears corrupted cached data that can corrupt the security handshake. On mobile, go to your device's app settings, find Roblox, and clear its cache.
5. Do a full clean reinstall of Roblox. Uninstall Roblox through Settings, then delete the leftover Roblox folder in %localappdata% and the ROBLOX Corporation folder if present. Download a fresh installer only from roblox.com (or the Microsoft Store / official app store) and install it. Fresh files guarantee nothing tampered with remains in your client.
6. Update Windows and your device drivers. Go to Settings, then Windows Update, and install every pending update. Then update your graphics drivers from NVIDIA, AMD, or Intel's official site. A broken or ancient driver can corrupt the client at runtime and make the security check fail even on an honest setup.
7. Whitelist Roblox in your antivirus and firewall. Open Windows Security, then Virus and threat protection, then Exclusions, and add the Roblox folder as an exclusion. Also check that your firewall lists Roblox as an allowed app. This stops security software from hooking into the client in ways that look like tampering.

Did this fix it? Quick checklist

• No exploit, cheat, or script tool is installed on your PC anymore — not even closed in the background
• Roblox-related browser extensions (Tampermonkey, RoPro, BTRoblox) are removed and the browser restarted
• Roblox cache cleared and a fresh copy installed from roblox.com or an official app store
• Windows, graphics drivers, and Roblox itself are all fully updated, and Roblox is whitelisted in your antivirus

If you followed these steps and 272 is gone, the flagged software was the cause. One honest warning before you celebrate: the 272 kick is Roblox's way of saying it caught you. If you keep using exploit tools, the next step beyond this error is real moderation — a warning or a ban on your account. Play it straight and this error becomes a non-issue. If the error somehow persists on a completely clean machine, your last resort is to contact Roblox support with a clean diagnostic — but that is rare.