Understanding Rainbow Six Siege Error Code 2-0X00000036
Error Code 2-0X00000036 in Rainbow Six Siege occurs when the Uplay (now Ubisoft Connect) session terminates unexpectedly during an active game. This is caused by the Ubisoft Connect overlay conflicting with Siege’s game networking, by the session token stored in the Ubisoft Connect cache becoming corrupted, or by the player’s ISP implementing a session hijacking detection that resets the connection as a security measure.
Why ISP Session Hijacking Detection Affects Siege
Some ISPs implement deep packet inspection (DPI) systems that monitor for patterns consistent with session hijacking — for example, when a game’s client sends heartbeat packets at regular intervals, DPI can misidentify this as a man-in-the-middle attack and reset the connection. When Ubisoft Connect’s session detects the connection reset, it terminates the player’s session with Error 2-0X00000036.
Resolving the Uplay Session Lost Error
Disabling Ubisoft Connect In-Game Overlay
Open Ubisoft Connect → Settings → Application, uncheck Enable in-game overlay. Close Ubisoft Connect completely (right-click tray icon → Exit). Launch Rainbow Six Siege from the Ubisoft Connect desktop app rather than from a shortcut. The overlay process being absent eliminates the conflict that causes session termination.
Clearing Ubisoft Connect Session Cache
Navigate to %UbisoftConnect%cache and delete all files in the folder. Additionally, navigate to %AppData% Ubisoft Connect and delete the sessions folder. Restart Ubisoft Connect — the session cache will be rebuilt from scratch, eliminating corrupted tokens as a potential cause.
Bypassing ISP Session Inspection with VPN
If disabling the overlay and clearing the cache do not resolve the error, ISP DPI is the likely cause. Use a VPN to encrypt your traffic — the VPN prevents the ISP’s DPI from inspecting packet patterns, eliminating the session hijacking false positive. WireGuard-based VPNs provide the lowest latency overhead, ensuring that the VPN does not introduce lag that disadvantages your gameplay.
Call to Action
Use the webs.ninja status engine to run a connectivity diagnostic that tests your ability to maintain a persistent connection to Ubisoft’s game servers over a 5-minute period. If the diagnostic shows connection resets during the test, your ISP is actively terminating the session — apply the VPN fix above. If the diagnostic shows a stable connection, the problem is the Ubisoft Connect overlay conflict, which the overlay and cache fixes resolve.