VAN 140: the game, Riot Client and Vanguard didn't start cleanly together

Connection Error: VALORANT has encountered a connection error. Please relaunch the client to reconnect. Error Code: VAN 140

A code Riot wrote for VALORANT players

Riot's VAN 140 article names VALORANT directly, in its explanation and in the example complaint it answers. League players still hit it, since the number comes from Vanguard and both games run the same anti-cheat. Riot's explanation puts the fault between programs, involving the game, the client and Vanguard together.

That framing is why its second step exists. Riot adds a compatibility change you won't find on any other VAN page: on both the game shortcut and RiotClientServices.exe, turn off fullscreen optimizations, tick run as administrator and let the application handle high DPI scaling. Riot's explanation is that Windows can apply launch behavior that gets in between the client, the game and Vanguard.

Where this clashes with a League fix

Keep a note of what you ticked. Riot's League article for getting stuck on the reconnect screen after champion select goes the other way: it has you open League of Legends.exe's Compatibility tab and clear every box, run as administrator included. The two articles name different files and answer different problems. Still, if VAN 140 goes away and that reconnect loop shows up afterwards, you know which settings you changed.

The list is short, too. Five steps, no clean boot and no connection checklist, so after the game reinstall Riot's next move is a ticket to Player Support with your logs.

Riot's fix, in Riot's order

1. Install every pending Windows update

   Open Settings, then Windows Update, and keep installing and restarting until it says you're up to date. Vanguard's checks lean on security components that ship in those updates, and optional driver updates are worth a look while you're there.

2. Change the compatibility settings on the game and the Riot Client

   Right-click the game's desktop shortcut, open Properties, then the Compatibility tab. Tick Disable fullscreen optimizations and Run this program as an administrator. Under Change high DPI settings, tick the override and set scaling to Application. Apply, then do the same to RiotClientServices.exe.

3. Set the vgc service to Automatic

   Vanguard has two parts: a driver that loads at boot and a Windows service called vgc. If the service isn't running when you press Play, the game closes.

   1. Press Win+R, type services.msc and press Enter.
   2. Find vgc in the list and double-click it.
   3. Set Startup type to Automatic. If the status says Stopped, click Start.
   4. Apply, OK, then restart the PC.

   The exception is Vanguard Pre-Check, Riot's opt-in mode where Vanguard only runs while a game is open. It needs Windows 11 25H2 or newer plus Secure Boot, TPM 2.0, IOMMU, VBS and HVCI, and if you're on it you shouldn't force the service to Automatic.

   Riot's guide: Set the vgc service to Automatic

4. Uninstall Vanguard, restart, and let the game reinstall it

   1. Close the game and exit the Riot Client from the system tray.
   2. Right-click the red Vanguard icon in the tray, choose Advanced, then Uninstall Vanguard. If the icon isn't there, search Windows for Add or remove programs and uninstall Riot Vanguard from the list.
   3. Restart the PC. Vanguard is gone if its tray icon doesn't come back.
   4. Open the Riot Client and launch the game. It reinstalls Vanguard and will ask for one more restart before Play unlocks.

   Riot's guide: Uninstall Vanguard, restart, and let the game reinstall it

5. Reinstall the game

   Uninstall from Windows' Installed apps list with the Riot Client closed. For a clean reinstall of League, Riot also has you delete the Riot Client folder under C:\Riot Games, the Riot Games folders under %localappdata% and %programdata%, and the League of Legends folder in Documents. That last one holds your replays, so copy them out first if you want them.

   Riot's guide: Reinstall the game

Related errors

• VAN 148
• VAN 1067
• Stuck at reconnect
• VAN 133

Source: Riot Games Player Support, Error VAN 140, updated July 16, 2026. Riot's steps are paraphrased here, not copied; checked September 25, 2026.