Since launch, a lot of Minecraft Dungeons II players cannot start the game, cannot sign in, or see an error code. The cause usually sits in Microsoft account authentication and Windows components rather than in the game itself. Working down this list sorts most cases out in a few minutes.
Identify the symptom first
| Symptom | Where to look |
|---|---|
| Error code, sign-in fails | Account and clock settings (steps 1 to 4) |
| No window ever appears, process exits on its own | Windows-side blocking and networking (steps 5 to 7) |
| Game starts, then drops to the lobby after a while | Online connection (step 7) |
| Nothing starts on SteamOS or Linux | Platform support (last section) |
Mojang has not published what error codes 0029, 0059 and 0064 mean. All three are reported alongside failed sign-ins, and the fixes people report are the same.
Step 1: wait and retry
Authentication servers are busiest right after release. Reviews describe sign-ins succeeding after several attempts. Try again after about 15 minutes before changing any Windows settings.
Step 2: update the Xbox app and sign in
Minecraft Dungeons II authenticates through a Microsoft account, and an outdated Xbox app breaks that.
- Open the Microsoft Store and check your library for updates
- Update the Xbox app and Xbox Game Bar
- Open the Xbox app and confirm you are signed in with the account that owns the game
Steam players need this too. If you are prompted to link your Steam account to your Microsoft account, follow the prompt.
Step 3: sync the Windows clock
Authentication fails when the clock drifts. Open date and time settings, turn on automatic time and automatic time zone, then sync now. This bites custom builds and dual-boot machines in particular, and a few minutes of drift is enough.
Step 4: repair Gaming Services
Gaming Services handles game licensing on Windows. When it breaks, the game does not start.
- Open Settings, then Apps, then Installed apps
- Find Gaming Services, open the three-dot menu, then Advanced options
- Run Repair, and if nothing changes, Reset
- Reboot
The same screen repairs the Minecraft Launcher. On Steam, verify the integrity of game files from the game’s properties.
If you set the game to run as administrator, turn that off. Elevated launches are reported to break Microsoft account sign-in.
Step 5: check whether Smart App Control is blocking it
If no window ever appears and the process shows up in Task Manager only to vanish, Windows 11 Smart App Control may be stopping execution. It blocks executables it does not consider trusted, which includes unsigned ones.
Check Event Viewer:
- Open Event Viewer
- Go to Applications and Services Logs, Microsoft, Windows, CodeIntegrity, Operational
- Look for event ID 3077
The setting lives in Windows Security, under App and browser control.
Step 6: look at the network
If the game still will not authenticate, traffic may not be reaching Microsoft’s servers.
- Disconnect any VPN or proxy and retry
- Allow the game and Gaming Services through your security software’s firewall
- Try a different DNS resolver temporarily
One Japanese review traced the failure to a stale static route left on the PC. The machine had previously hosted a Minecraft server, the router was later replaced, and the old route stayed behind.
If you have ever hosted a server on that PC, run route print and look for routes you do not recognise. Remove them with route delete.
The same applies to machines where port forwarding or DMZ settings were tested.
Step 7: disconnects during play
Some players report being dropped to the lobby every half hour with a message about the internet connection being lost. That points at the service side rather than your PC, so the options at home are limited.
- Switch to a wired connection
- Enable UPnP on the router
- Avoid large downloads on the same line while playing
The game expects to be online. Reviews report that single player will not start without a connection.
Why SteamOS and Linux fail
On SteamOS, including Steam Deck, the game widely fails to start under standard Proton because it depends on Windows Gaming Services. Community-built Proton versions have reportedly worked, but none of that is supported, and as of September 30, 2026 the game carries no Steam Deck compatibility badge.
If none of it works
| Situation | Next move |
|---|---|
| Error codes keep coming | Reinstall the game and the Minecraft Launcher |
| Only one account fails | Sign in with a different Microsoft account to isolate it |
| Considering a refund | Steam’s rule is within 14 days of purchase and under 2 hours played, so decide before that window closes |
No patch notes exist as of September 30, 2026. If you plan to wait for a fix, check the Minecraft Dungeons II category on the official feedback site for your symptom.
FAQ
- Q. Do Game Pass players see these errors too?
- A. Yes. The authentication path is the same, so start with the Xbox app update and sign-in check.
- Q. Does each error code need a different fix?
- A. The reported fixes for 0029, 0059 and 0064 overlap completely, which is why this guide sorts by symptom instead.
- Q. Can I play offline?
- A. Reviews report that single player will not start without an internet connection, so do not buy it as an offline game.
- Q. Should I just turn Smart App Control off?
- A. No. It cannot be turned back on. Only consider it when event ID 3077 actually appears in your logs.
- Q. Will it work on Steam Deck?
- A. As of September 30, 2026, most reports say no on a stock setup, and there is no compatibility badge.
If the controls are the problem rather than the launch, see Minecraft Dungeons II has no WASD movement. Prices and platforms are in Minecraft Dungeons II: release date, price, platforms, and the Sift.
日本語版: Minecraft Dungeons IIが起動しない・エラーコードの直し方
Sources, checked on 2026-09-30: 50 recent Steam user reviews in English and Japanese, the Minecraft Dungeons II Steam store page, Microsoft’s support documentation on Smart App Control, published fixes for error code 0064 (2026-09-29), and our own testing (2026-09-29).