There are three primary causes for this error:
Automatic file verification – either through Ubisoft Connect or Steam – is the most reliable fix, because it replaces the exact correct version of the DLL without risking malware or version mismatches.
If the error persists after verifying, your antivirus is almost certainly the cause. Add exclusions and re-verify.
To fix the uplay_r1_loader64.dll error in Assassin's Creed Unity
, you generally need to restore the file from your antivirus quarantine or manually replace it from your game's internal backup folders. This error is usually a "false positive" where Windows Defender or other antivirus software flags the file as a threat and blocks it. 1. Restore the File from Windows Security
Most of the time, the file isn't actually "missing"—it's just being held hostage by your antivirus. Open Windows Security and go to Virus & threat protection. Click on Protection history.
Look for a "Severe" threat or blocked item that mentions uplay_r1_loader64.dll. Click Actions and select Restore.
Crucial Step: Immediately add your Assassin's Creed Unity folder to the "Exclusions" list in your antivirus settings so it doesn't delete the file again the next time you launch the game. 2. Use the Built-in Backup (NoDVD Folder)
If you are using a specific version of the game (like a repack), the installer often leaves a backup of the necessary DLLs inside the game directory. Go to your main Assassin's Creed Unity installation folder. Look for a folder named NoDVD or SKIDROW. Inside, you should find a copy of uplay_r1_loader64.dll. There are three primary causes for this error:
Copy it and Paste it directly into the main game folder where the .exe is located. 3. Verify Game Files (Official Versions)
If you own the game on Steam or Ubisoft Connect, use the built-in repair tool to download the correct official file.
Steam: Right-click the game > Properties > Installed Files > Verify integrity of game files.
Ubisoft Connect: Go to the game's page > Properties > Verify files. 4. Manual Download (Last Resort)
If the file is completely gone and you don't have a backup folder, you can download it from a repository like DLL-files.com.
Warning: Only download from reputable sources. Once downloaded, extract the .dll and paste it into the game's main installation directory.
Common Pitfall: If you just replace the file without adding a "Folder Exclusion" in your antivirus, the game might crash or the file will disappear again within seconds of you trying to play. If you're still having trouble, let me know: Are you using the Steam, Ubisoft, or a repack version? What antivirus are you running?
Does the error say the file is "missing" or is it a "procedure entry point" error? If the error persists after verifying, your antivirus
I can give you a more specific walkthrough based on those details!
uplay_r1_loader64.dll Assassin's Creed Unity is typically caused by your antivirus software—such as Windows Security Malwarebytes
—mistakenly flagging the file as a threat and quarantining it. 1. Restore the File from Windows Security
If you are using Windows 10 or 11, the file is likely sitting in your protection history. Windows Security Virus & threat protection Protection history
Look for "Quarantined threat" or "Blocked app" entries related to uplay_r1_loader64.dll Select the entry, click , and choose 2. Manual Recovery from Game Folders
Many versions of the game include a backup of this file within the installation directory. Go to your main Assassin's Creed Unity installation folder. Look for a folder named Inside, locate the uplay_r1_loader64.dll file (and sometimes skidrow.ini these files and them directly into the main game directory where the file is located. 3. Add an Exclusion (Prevent Recurring Errors)
To prevent your antivirus from deleting the file again after you restore it, you must whitelist the game folder. Windows Security Virus & threat protection settings Manage settings Scroll down to Exclusions Add or remove exclusions Add an exclusion , and choose your Assassin's Creed Unity installation folder. 4. Verify Files (Official Versions) If you own the game officially on Ubisoft Connect
, do not download replacement DLLs from third-party sites, as these are often meant for "cracked" versions and may cause crashes. Ubisoft Connect : Click the game, go to Properties , and select Verify files : Right-click the game > Properties Installed Files Verify integrity of game files mention it to help fellow assassins.
Difficulty: Very Easy | Success Rate: 40% (But worth trying)
Many users report that this error appears only on the first launch attempt after installation. A simple workaround exists.
Corrupted or missing files are the next most likely culprit.
Sometimes the launcher itself is the problem.
Before fixing the error, it helps to understand what this file is.
The error appears when: The game finds the DLL missing, corrupted, blocked by antivirus, or when the Ubisoft Connect client fails to launch it correctly.
The uplayr1loader64.dll error in Assassin’s Creed Unity is almost never a missing file—it’s usually a permission, antivirus, or launcher communication issue. Starting with the simplest fixes (Run as Admin, Verify files, Disable AV) will solve 90% of cases.
For the remaining 10%, Solutions 6 (delete version.txt) and 8 (Clean Boot) are your best friends.
Now get back to the French Revolution, and may your co-op sessions lag no more.
Did this article help you? Share which solution worked in the comments below. If you found another fix, mention it to help fellow assassins.