![\"Critical](\"https:\/\/seminarsonly.com\/news\/wp-content\/uploads\/2026\/07\/critical-error-featured.jpg\")
<\/p>\n
Quick answer<\/p>\n
The “critical error has occurred” message usually means an overlay app (Discord, MSI Afterburner, GeForce Experience), an outdated GPU driver, or a stalled Vanguard\/VGC service is conflicting with the game process. Close overlay apps, run the game as administrator, update your graphics driver, and restart the Vanguard (Valorant) or VGC (League\/TFT) service. That resolves the error for most players within a few minutes.<\/p>\n<\/div>\n
TLDR<\/p>\n
- \n
- Close Discord overlay, MSI Afterburner, RivaTuner, and screen recorders before launching<\/li>\n
- Right click the game exe and select “run as administrator”<\/li>\n
- Update your GPU driver from NVIDIA, AMD, or Intel directly<\/li>\n
- Restart the Vanguard service (Valorant) or VGC service (League and TFT) in services.msc<\/li>\n
- Reinstall the game only if every other fix has failed<\/li>\n<\/ul>\n<\/div>\n
Jump to a section:<\/strong><\/p>\n
- \n
- What this error actually means<\/a><\/li>\n
- Common causes at a glance<\/a><\/li>\n
- Quick fixes to try first<\/a><\/li>\n
- Advanced fixes<\/a><\/li>\n
- Game specific notes<\/a><\/li>\n
- When to contact Riot support<\/a><\/li>\n
- Frequently asked questions<\/a><\/li>\n<\/ul>\n
What this error actually means<\/h2>\n
A critical error is a fault serious enough that Windows or the game engine cannot safely continue running the process, so it force closes to avoid corrupting data or crashing your whole system. Riot’s client shows this specific dialog, with an option to generate a crash dump, when the League of Legends, Valorant, or TFT process hits an unrecoverable conflict. The message itself does not name a cause, which is why the same dialog can appear for a driver issue, an overlay conflict, a corrupted file, or a background service problem.<\/p>\n
Common causes at a glance<\/h2>\n
The table below ranks causes from most to least common, based on Riot’s own support guidance and widely reported player fixes.<\/p>\n
\n\n
\n Cause<\/td>\n How common<\/td>\n Fastest fix<\/td>\n<\/tr>\n \n Overlay software (Discord, Afterburner, recorders)<\/td>\n Very high<\/td>\n Close all overlay apps via Task Manager<\/td>\n<\/tr>\n \n Outdated or mismatched GPU driver<\/td>\n High<\/td>\n Update driver from NVIDIA, AMD, or Intel<\/td>\n<\/tr>\n \n Vanguard or VGC service not running<\/td>\n High<\/td>\n Set service to automatic in services.msc<\/td>\n<\/tr>\n \n Fullscreen optimization conflicts<\/td>\n Medium<\/td>\n Disable fullscreen optimization in compatibility settings<\/td>\n<\/tr>\n \n Corrupted game files or config<\/td>\n Medium<\/td>\n Repair or reinstall the game client<\/td>\n<\/tr>\n \n Firewall or antivirus blocking the game<\/td>\n Low to medium<\/td>\n Allow the game through Windows Defender Firewall<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Quick fixes to try first<\/h2>\n
Work through these in order. Most players resolve the error in the first three steps.<\/p>\n
1. Close overlay and recording software<\/h3>\n
Open Task Manager and end tasks for Discord, MSI Afterburner, RivaTuner Statistics Server, OBS, or any screen recording tool. Overlays hook directly into the game’s rendering process, and that hook is one of the most frequent triggers for this crash.<\/p>\n
2. Run the game as administrator<\/h3>\n
Right click the game’s executable file, open Properties, go to the Compatibility tab, and check “run this program as administrator.” This gives the process the permissions it needs to write crash logs and access system resources without being blocked.<\/p>\n
3. Disable fullscreen optimization<\/h3>\n
In the same Compatibility tab, tick “disable fullscreen optimizations.” Windows’ own fullscreen handling sometimes conflicts with how Riot’s client manages the display, and disabling it removes that conflict entirely.<\/p>\n
4. Update your graphics driver<\/h3>\n
Download the latest driver directly from your GPU manufacturer rather than relying on Windows Update, which can lag behind. Visit NVIDIA’s official driver page<\/a> for GeForce cards, or the equivalent AMD or Intel driver hub for other hardware.<\/p>\n
5. Restart your PC<\/h3>\n
A full restart clears stuck background processes and memory conflicts that build up over long uptime sessions. It sounds basic, but Riot’s own support team lists it as a genuine fix, not just a formality.<\/p>\n
Google Health API Error 401 Unauthorized: How to Fix It (2026 Guide)<\/a><\/p><\/blockquote>\n
- Common causes at a glance<\/a><\/li>\n
- What this error actually means<\/a><\/li>\n