The uplay_r1_loader.dll file is a critical Dynamic Link Library component of Ubisoft's Uplay (now Ubisoft Connect
If the file is completely gone, you can manually replace it to restore functionality. Download from Trusted Sources
error, it is likely due to the rebranded Ubisoft Connect launcher or your antivirus quarantine. 1. Restore/Replace the DLL File Antivirus Check:
As a last resort, you can manually replace the missing file.
Often the launcher itself is broken.