Repairing a broken Roblox install

Force a clean reinstall of the Roblox client through Agentstrap.

Sometimes the Roblox install gets into a state where the client is missing, half-extracted, or fails to start no matter what you change. Agentstrap can force a clean reinstall.

Force a reinstall

Turn on forced reinstall. Settings → Bootstrapper → Force reinstall, then press Save.
Launch Roblox. Use Command Center → Launch Roblox.
Wait for it to finish. The Roblox package is downloaded again and extracted over the existing files.
Check the result. Command Center → Refresh status re-checks whether the player executable is present.

The flag is one-shot. Forced reinstall applies to the next launch and then resets itself, so you don't have to remember to turn it back off.

When that's not enough

If a forced reinstall doesn't fix it, the install folder itself is probably damaged. Delete the version folder and let Agentstrap download Roblox again from scratch.

%LOCALAPPDATA%\Agentstrap\Versions\

Close Roblox and Agentstrap first, then delete the contents of that folder. The next launch downloads and extracts a fresh copy. This does not touch your settings or your mods, because those live outside the Versions folder.

This needs a working internet connection and some disk space. A full Roblox download is a few hundred megabytes.

Deleting the whole install

If you want a completely clean slate, delete the whole %LOCALAPPDATA%\Agentstrap folder and run the installer again. You will lose your settings and mods. See Uninstalling Agentstrap.

Confirming the repair worked

Run Diagnostics afterwards. The Roblox installation and Roblox version state checks should both come back clean.

Agentstrap 2.11.4 · These docs describe Agentstrap 2.11.4. Features marked new are not present in upstream Bloxstrap.