Valorant Error Code 51 Explained: What Triggers It And What Actually Fixes It

Valorant does not throw Error Code 51 for no reason. It throws it when the client cannot complete the connection handshake it needs to enter a match, and the reason it cannot varies more than most players expect. The fix that works for one player will do absolutely nothing for another, because the underlying trigger is different.

This guide walks the four realistic causes in the order they actually show up, so you can match the fix to the trigger instead of guessing.

Trigger 1: Antivirus Or Security Software Blocking Riot

By far the most common cause of Error 51 on Windows machines is third-party antivirus software incorrectly flagging a Riot process. It is common enough that even Riot's own support acknowledges antivirus interference as a leading cause. It usually shows up the first time you play after an antivirus update, or after installing a new suite like Kaspersky, Bitdefender, or a corporate security agent.

The test is simple: temporarily disable your third-party antivirus (not Windows Defender, that one rarely conflicts) and launch Valorant again. If the error is gone, you have identified it.

Recommended fix: Add Riot Client, Valorant.exe, and Vanguard to your antivirus's exception list. Do not leave the antivirus off permanently. If your antivirus has an aggressive gaming mode, use it, because those modes usually skip the deep inspection that trips Vanguard.

Corporate machines have an extra wrinkle here. If Valorant is being played on a laptop with company-installed security agents, the fix may not be available to you without IT involvement. This is worth knowing before you spend an hour trying network-side fixes that will not help.

Trigger 2: Riot Client Session In A Bad State

A smaller but real category of Error 51 comes from the Riot Client itself being stuck in a broken login state, especially after a patch day or a server restart. The signature here is that everything else on your PC is working fine, no antivirus warning, and yet the game refuses to move past the connection step.

Recommended fix: Fully quit the Riot Client from the system tray, wait a moment, and relaunch. If that does not work, sign out of the Riot Client and sign back in. This clears the stuck session token, which is often what the actual problem was.

If you have Vanguard installed, restarting the PC once after clearing the client tends to resolve residual cases, because Vanguard fully reloads on boot and stops being a variable.

Trigger 3: A Bad Path Between You And The Riot Server

When antivirus has cleared and the client is up to date, recurring Error 51 is almost always a network routing issue. Normally, ISPs in each region provide players with a route to Riot servers, but that route also carries other traffic. As a compromise, it is not necessarily optimal, and you may also encounter random congestion or instability.

The difficulty in adjusting the route is that players can hardly intervene:

1. Router optimization is basically limited to adjusting traffic within your home network.
2. DNS adjustments, in essence, public DNS cannot deliver optimal results.
3. ISP adjustments: even upgrading to an expensive dedicated line cannot guarantee effectiveness for every game.

Recommended fix: So you still need to rely on a game routing tool, such as GearUP. It offers the freedom to choose global routes, and you may not even need to select one, since it can automatically match routes based on algorithms without requiring you to open ports, change DNS, or perform any configuration. The advantage of automation is fewer errors and greater accuracy than manual methods.

GearUP also provides multi-platform solutions. On PC it is a two-step operation:

1. Find Valorant in GearUP.
2. After starting optimization, leave it running in the background, then launch the game.

Consoles can be optimized through a router plugin:

• ASUS partner router user guide
• ZTE partner router user guide
• OpenWrt router installation guide
• Steam Hardware Plugin Installation Guide

Trigger 4: Server-Side Outage On Riot's End

Sometimes Error 51 really is Riot's fault. This is the least common cause, but it is worth confirming before spending time on your own machine.

Recommended fix: Check Riot's official status page for Valorant, which lists per-region service health. Downdetector's live report is a useful secondary confirmation. If hundreds of players are reporting the same failure at the same minute, wait for Riot instead of restarting your PC three times.

During a real outage, no local fix will work. The correct move is to close the game and wait, or switch to another region if your account has one available (though this is rare in Valorant).

The DEP Fix People Recommend, And When It Actually Applies

Many older guides suggest adjusting Windows Data Execution Prevention for Valorant. This can help in a narrow case: extremely old Windows installations, or systems that have picked up DEP misconfigurations from earlier third-party tools. On a modern, up-to-date Windows 10 or 11 install, DEP is almost never the cause of Error 51.

If you want to try it: open sysdm.cpl, go to the Advanced tab, click Settings under Performance, open the Data Execution Prevention tab, and add the Riot executables to the exception list. Restart afterward. If nothing changes, revert it. Leaving DEP tweaks in place "just in case" is not helpful and slightly increases your exposure to memory-based exploits.

The Fastest Path Through All Four Triggers

If you want a simple order that catches most cases quickly:

1. Check Riot's status page. If Valorant is down for your region, stop here and wait.
2. Restart the Riot Client fully from the tray. Log out and back in if the restart alone does not clear it.
3. Temporarily disable third-party antivirus and try again. If it works, add the Riot processes to your exception list.
4. If it still happens, and especially if it happens more during evenings than mornings, try a route optimizer to bypass the bad ISP path.
5. DEP and driver reinstalls are last-resort. Only touch them if the previous four steps do nothing.

Most players get through this list in under ten minutes and identify the exact cause. That is more useful than trying every fix from a checklist without knowing which one applied.

After The Fix

Once Error 51 stops appearing, Valorant should behave normally: fast queue times, clean match starts, no repeated handshake failures. If it returns days later at a different time of day, the underlying trigger has changed, possibly an antivirus definition update or an ISP routing change, and the same diagnostic order still works. Error 51 is a family of symptoms, not a single bug, and the fastest way to handle it is to keep the four triggers in mind rather than treating each occurrence as its own mystery.