Problem: Battle.net “Update Agent went to sleep” (BLZBNTBNA00000005) breaking Blizzard games on Steam Deck & Linux (often stuck at 45% install)

Published: 2026-01-17 12:00 (local time)

Quick Summary

Many Steam Deck and Linux players report Battle.net failing with “Update Agent went to sleep” (BLZBNTBNA00000005), preventing installs, updates, and game launches.
A common related symptom: Battle.net installation hanging or failing around “45%” when installed via Lutris/Wine.
There isn’t one universal fix; what works depends on your Proton/Wine runner, install method (Steam vs Lutris), and sometimes security software.
The most repeated community workaround is switching to Proton 10 (beta) or Proton Experimental for the Battle.net launcher.
If you need to play immediately, bypassing the launcher (where possible) or using a Windows PC/VM/streaming can keep you playing while the ecosystem stabilizes.

What’s happening

Players trying to run Blizzard games through the Battle.net desktop app on Steam Deck and Linux (commonly via Steam compatibility tools like Proton, or via Lutris/Wine) are hitting a persistent launcher failure: Battle.net can’t communicate with its update agent and shows “Update Agent went to sleep” (error code BLZBNTBNA00000005). Blizzard’s own description of the error indicates the desktop app failed to communicate with the Battle.net Update Agent, which is required for installing, updating, launching, and uninstalling games.

In community threads, the issue often appears suddenly after a previously working setup, then persists through reinstalls. A second, very common symptom reported alongside the “agent asleep” message is the Battle.net installer stalling around 45% (especially when installed through Lutris). Multiple users across different Linux distributions report the same 45% stall, suggesting a widespread compatibility/regression pattern rather than a single user’s misconfiguration.

Who’s affected: primarily Steam Deck players and Linux desktop users relying on Proton/Wine layers, especially those installing Battle.net via Lutris or adding Battle.net as a non-Steam game. Windows users can see the error too, but the “45% installer stall” pattern shows up most frequently in Linux/Wine reports.

Likely causes (what research suggests)

Compatibility/regression between Battle.net updates and specific Proton/Wine builds: Multiple reports indicate the problem started “out of nowhere” and is resolved by switching Proton/Wine versions, implying an interaction between a Battle.net update and certain runner behaviors.
Installer/update-agent communication issues under Wine/Proton: Blizzard’s own support article frames it as a failure to communicate with the update agent; on Linux, this can be amplified by how Wine implements networking, services, permissions, and background processes.
Security software / permission interference (more common on Windows, but not impossible elsewhere): Blizzard suggests checking security software exceptions and permissions. Some users historically reported security tools interfering with the agent behavior.
Network reliability isn’t the main driver in most reports: Many affected users report otherwise stable connections and other apps working; however, intermittent connectivity can still worsen the symptom.

Solutions & Workarounds

1) Switch Battle.net to Proton 10 (Beta) in Steam (most repeated fix on Steam Deck)

Who it helps: Steam Deck users running Battle.net as a non-Steam game through Steam.

Steps:
- In Steam, find your Battle.net “non-Steam game” entry.
- Open Properties → Compatibility.
- Check Force the use of a specific Steam Play compatibility tool.
- Select Proton 10 (Beta) (if not visible, opt into Steam’s beta channel, then re-check compatibility tools list).
- Fully reboot the Steam Deck (some users report it only works after a restart), then launch Battle.net again.
Risks / tradeoffs: Beta Proton can introduce new issues (launcher opens then closes, controller mappings differ, shader cache rebuilds).
Stop and contact support when: You still get BLZBNTBNA00000005 after switching Proton and rebooting; at that point, gather logs and check Blizzard’s official troubleshooting steps and forums.

2) Try Proton Experimental (or a different stable Proton) if Proton 10 Beta fails

Who it helps: Steam Deck/Linux users where Proton 10 Beta causes immediate launcher exit or new crashes.

Steps:
- Repeat the Compatibility steps above, but select Proton Experimental.
- Launch Battle.net; if it fails, try one additional known-good Proton version (one at a time), rebooting between attempts.
Risks / tradeoffs: Experimental changes frequently; today’s fix can be tomorrow’s regression.
Stop and contact support when: Multiple Proton versions fail the same way; continuing to randomize versions can waste time without improving signal.

3) If using Lutris: change the runner (Wine/Proton build) and avoid the “stuck at 45%” trap

Who it helps: Linux desktop users installing Battle.net via Lutris, especially those stuck at 45% during install.

Steps:
- In Lutris, open the Battle.net entry (or installer) configuration.
- Change the Wine runner to a different build (community reports mention success after switching away from one runner and onto another staging/TKG/alternative build).
- Re-run the installer and re-test login/update.
Risks / tradeoffs: Runner swaps can break previously installed games in that prefix; back up the prefix before major changes.
Stop and contact support when: You repeatedly stall at 45% across multiple runners; then you’re likely waiting on a compatibility fix and should use a temporary “play now” workaround.

4) Bypass the Battle.net launcher (where possible) to play immediately

Who it helps: Players who already have a Blizzard game installed and can launch the game executable directly (varies by title and account requirements).

Steps:
- Locate the game’s main executable inside the existing install folder.
- Add that executable to Steam as a non-Steam game.
- Force a Proton version that you know works for the game itself.
- Log in in-game if prompted (some titles will still require Battle.net services for authentication).
Risks / tradeoffs: Not all Blizzard games support clean bypass; updates may still require Battle.net; some features (patching, repair, account services) may be unavailable.
Stop and contact support when: The game refuses authentication or requires the launcher for critical updates.

5) Follow Blizzard’s official BLZBNTBNA00000005 steps (especially security/permissions checks)

Who it helps: Everyone, but especially Windows dual-booters or Linux users who suspect permissions/security layers are interfering.

Steps:
- Update OS and drivers.
- Temporarily disable or whitelist security tools/firewalls for Blizzard/Battle.net components (then re-enable after testing).
- Try reinstalling the Battle.net app after confirming your system isn’t blocking the update agent.
- If nothing works, use Blizzard’s recommended escalation path (tech support forums/support contact).
Risks / tradeoffs: Disabling security tools reduces protection; only do it briefly for testing and restore immediately.
Stop and contact support when: You’ve completed the official checklist and can reproduce the failure consistently.

6) “Keep playing” fallback: run Blizzard games on Windows (VM/dual-boot) or stream from a Windows PC

Who it helps: Players blocked for days and willing to trade convenience for reliability.

Steps:
- Use a Windows install (dual boot or a dedicated machine).
- Install Battle.net normally on Windows.
- If you want handheld play, stream the game to your device from the Windows machine.
Risks / tradeoffs: Setup time, storage needs, possible performance/latency; not a true “fix,” but a dependable workaround.
Stop and contact support when: You confirm the issue is only in Proton/Wine; then you can monitor for a community/official compatibility resolution.

Prevention (so it doesn’t come back)

Keep at least one known-good Proton/Wine runner installed so you can roll forward/back quickly if an update breaks the launcher.
Back up your Wine prefix (or Steam compatibility data) before major launcher changes.
Avoid repeated full reinstalls as your first step; try runner switching first to preserve working game files.
Document what worked: Proton version, install method, and any special launch flags—so you can restore fast after updates.

FAQ

Q: Is BLZBNTBNA00000005 a Blizzard server outage?
A: Blizzard notes it can be related to failures communicating with the update agent, and can sometimes be caused by service outages, but community reports strongly suggest a compatibility/regression component on Linux/Steam Deck setups.

Q: Why does the installer hang at 45%?
A: Many Linux/Lutris users report a consistent stall at ~45% during Battle.net installation. This commonly improves when changing the Wine/Proton runner, implying an environment/runner interaction rather than a single corrupt download.

Q: Should I uninstall everything (including games) and reinstall?
A: Not first. Many users report reinstalls don’t help (and can waste hours). Try runner/Proton changes before deleting large game installs.

Q: Proton 10 makes Battle.net open then instantly close—what now?
A: Try a full system reboot, then try Proton Experimental. If it still closes, switch strategies (Lutris runner change, bypass the launcher, or a Windows fallback).

Q: Can I bypass Battle.net and still play?
A: Sometimes. Some users launch a game’s executable directly through Steam/Proton, but it depends on the game and whether it requires Battle.net services for login/updates.

Q: When should I stop troubleshooting?
A: If you’ve tried two or three runner/Proton options, rebooted, and followed Blizzard’s official steps with no change, it’s time to use a fallback (Windows/streaming) and escalate via official support/forums.