uplay_r164.dll Error in Windows: Causes and Quick Fix

What the uplay_r164.dll Error Means

The uplay_r164.dll error appears when attempting to launch a game via the Ubisoft Connect client. The full message typically looks like this: "The program can't start because uplay_r164.dll is missing from your computer. Try reinstalling the program to fix this problem."

The uplay_r164.dll file is a dynamic library responsible for integrating the game with the Ubisoft ecosystem (authentication, cloud saves, overlay, achievements). When Windows cannot find this file or fails to load it into memory, the game process terminates immediately.

Common Causes

1. Corrupted client or game update. A patch download failed, partially overwriting or deleting the library.
2. Antivirus false positive. Security solutions sometimes flag game DLLs as threats and automatically quarantine them.
3. Corrupted Microsoft Visual C++ runtime. uplay_r164.dll depends on system runtimes. If they are missing or damaged, loading fails.
4. Permission restrictions. The client is running under a standard user account, while the game folder requires administrator rights to read libraries.

Solutions

Solution 1: Verify Game Files in Ubisoft Connect

The safest and fastest method. The launcher will compare local file hashes with server versions and redownload missing elements.

1. Open Ubisoft Connect and navigate to the Games section.
2. Find the problematic game, right-click its tile.
3. Select Properties → go to the Files tab.
4. Click the Verify files button and wait for the process to complete.
5. After it finishes, try launching the game.

Solution 2: Reinstall Ubisoft Connect

If verification didn't help, the issue may lie with the launcher itself, which may be unpacking libraries incorrectly.

1. Open Windows Settings → Apps → Installed apps.
2. Find Ubisoft Connect, click ⋮ (or Modify/Uninstall), and proceed with removal.
3. Restart your computer.
4. Download a fresh installer from the official Ubisoft website and run it.

💡 Tip: Uninstalling the launcher does not delete your installed game files unless you manually select that option. Your cloud progress will also be preserved.

Solution 3: Install Latest Visual C++ Redistributables

Missing system components can block uplay_r164.dll from loading even if the file physically exists on disk.

1. Go to the official support page: Latest supported Visual C++ Redistributable.
2. In the Visual Studio 2015, 2017, 2019, and 2022 section, download both files: x64 and x86.
3. Run both installers sequentially and follow the wizard prompts.
4. Restart your system.

⚠️ Important: Never download VCRuntime or msvcp packages from torrents or driver packs. Use only the Microsoft portal to avoid malware injection.

Solution 4: Antivirus Exclusion and Permission Check

Security software may have silently moved the file to quarantine. You need to restore it and grant access.

1. Open your antivirus interface and locate the Quarantine, Threat History, or Protected Files section.
2. Find uplay_r164.dll in the list, select Restore.
3. Add the folder C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher to your Exclusions list.
4. Launch Ubisoft Connect by right-clicking its shortcut → Run as administrator.

Prevention

To prevent the error from recurring, follow simple system maintenance rules. Regularly update your graphics card drivers using official utilities (GeForce Experience or AMD Adrenalin). Disable the automatic compression feature in the Program Files folder properties—it often blocks access to game libraries. When installing antivirus software, immediately add Ubisoft Connect to the whitelist so protective algorithms won't scan files in real-time during game launches.