Valorant install + Vanguard timing

Valorant ships with Riot Vanguard, a kernel-mode anti-cheat that loads at Windows boot and refuses to start the game if anything looks off. The Nimbus Valorant tab handles the timing for you, but you have to launch in the right order, and you have to accept the one-time risk notice before the Launch button unlocks.

Pre-Vanguard timing (the most important step)

Vanguard scans memory the moment it starts. If Nimbus is already injected when Vanguard initializes, Vanguard refuses to load and Valorant won't start. The fix is simple: start Nimbus before the Riot Client, not after.

1. Cold boot Windows. If Vanguard ran earlier today, restart — it's cheaper than fighting a stale Vanguard session.
2. Close the Riot Client and any RiotClientServices.exe tray icon. Confirm in Task Manager that no Riot processes are running.
3. Launch the Nimbus loader, sign in, and open the Valorant tab.
4. Tick the acknowledgement (one time only — see below), then click Launch.
5. Nimbus stages the payload, then opens the Riot Client itself. Don't open the Riot Client manually first.

The one-time acknowledgement

The first time you open the Valorant tab, the Launch button is disabled. You'll see a red advisory panel describing the Vanguard risk and a checkbox labelled “I understand the Vanguard risk and want to proceed.” Ticking it persists a flag at:

%LOCALAPPDATA%\Nimbus\valorant_vanguard_ack.flag

Once that flag exists, the Launch button stays unlocked for future sessions. Sign Out (or the customer Wipe action) deletes the flag, so you'll be asked to acknowledge again on the next sign-in.

Troubleshooting

“Vanguard not loaded” or “Vanguard requires a system restart”

This is by far the most common Valorant error. It almost always means Vanguard tried to initialize while Nimbus was already in memory, or Vanguard was killed mid-session and is now in a half-loaded state.

• Restart Windows. Then start with Nimbus, not the Riot Client.
• Don't use the Riot Client's tray-icon “Start Valorant” shortcut while Nimbus is staged — it bypasses the timing window.
• If Vanguard says it's disabled, open Services (services.msc) and confirm vgc is set to Automatic. The Nimbus spoofer never disables vgc; if it's off, some other tool did it.
• Antivirus interference: if Defender or a third-party AV quarantined a Vanguard component, Vanguard won't load cleanly. See Antivirus help for the standard exclusions.

“Riot Client not detected”

Nimbus probes for C:\Riot Games\Riot Client\RiotClientServices.exe and the registry entries Riot drops on install. If neither shows up, the preflight blocks Launch.

• Confirm Valorant + the Riot Client are actually installed. The Nimbus loader does not ship the Riot Client.
• If you installed to a custom path, the registry entry should still be there. Try opening the Riot Client once by hand, then close it and retry.
• Repair install: from Settings → Apps, find Riot Client and run Repair. Most “not detected” cases are a half-finished install from a previous uninstall.

Screenshots

Screenshot placeholders below (captured from the Nimbus loader, Valorant tab):

• valorant-tab-ack.png — red advisory panel + acknowledgement checkbox + greyed-out Launch button
• valorant-tab-ready.png — post-ack state, red accent (#E03B49), Launch button armed
• valorant-vanguard-error.png — example of the Vanguard error modal Riot shows on bad timing

Still stuck?

File a ticket via Support with the exact error text and the loader boot log (Settings → Export boot log to Desktop). Include whether you cold-booted before launching — that one detail resolves the majority of Vanguard tickets.