Quick answer
As of October 1, 2026, Bandai Namco has not published a definition, a single cause or a patch for "Error 01" (also shown as UE Live Error 01). Its September 29 Product Notice says the team has received reports of "unexpected crashes" in the Steam version and is investigating them.[1]
The notice gives two official checks. First, use the recommended graphics driver version that the game shows at launch. Second, keep 16 GB or more free on the SSD where the game is installed, with virtual memory turned on in Windows.[1] Try these two before anything else.
What the developer has confirmed so far
| Topic | Official status (Oct 1, 2026) | Source |
|---|---|---|
| Crashes on the Steam version | Acknowledged; the team says it is "currently investigating the reports" | Product Notice, Sep 29[1] |
| A fix or patch for crashes | None announced. The notice offers checks that "may help improve stability in certain environments" | Product Notice[1] |
| What "Error 01" means | No official definition found in the game's Steam announcements | Steam announcements[1][2] |
| Online error ST-3100001 | Explained: it "appears when communication with the game server is lost" | Error code notice, Sep 30[2] |
| Flight stick problems | Acknowledged in a separate notice; see our HOTAS page | Flight Stick Support Update[3] |
The "UE" in UE Live Error 01 points to the engine: Bandai Namco says the game runs on Unreal Engine 5.[4] A signed troubleshooting guide by Daniel Hidalgo (xboxplay.games, Sep 30) calls it an Unreal Engine error and says "this error usually does not have one specific reason".[5] That fits the official picture: there is no single confirmed cause yet.
What the crashes look like
On September 30, ixbt.games summarised what players were reporting in Steam discussions. Those players describe crashes during intro scenes, after flight begins and during mission replays. In some cases, the game "gives error 01 and closes before the player even gets into the cockpit."[6] These are player reports, not an official diagnosis.
Fix order: what to check, and who recommends it
Work down this list in order. The first two rows are hardware gates: no setting fixes them. Rows 3 and 4 come from the developer. Rows 5 and 6 come only from a signed third-party guide, so treat them as things to try, not confirmed fixes.
| # | Check | When it applies | Who says so |
|---|---|---|---|
| 1 | Your GPU supports hardware ray tracing and DirectX 12 with Shader Model 6.6, and the game is on an SSD | Every PC. The store page lists all three as required | Steam store page[7] |
| 2 | You are on Windows 11 (64-bit) | Every PC. Both spec tiers list Windows 11 | Steam store page[7] |
| 3 | Install the recommended graphics driver "indicated when launching the game" | Any crash on Steam | Official notice[1] |
| 4 | Keep 16 GB+ free on the install SSD and keep virtual memory enabled in Windows | Any crash on Steam | Official notice[1] |
| 5 | In Steam, open the game's Properties > Installed Files and run Verify integrity of game files | The game will not open or closes at startup | Signed guide[8] |
| 6 | Quit the game, copy GameUserSettings.ini to keep a backup, then delete the original so the game makes a fresh one | Error 01 at launch, during shader compiling or in a cutscene | Signed guide[5] |
| 7 | Online only: error ST-3100001. Sync the time on Windows and test again | The ACE COMBAT ONLINE connection drops | Official notice[2] |
The guide puts GameUserSettings.ini in the game's folder under %LOCALAPPDATA%, inside Saved > Config > Windows.[5] Keep the copy so you can restore your graphics settings if the reset changes nothing.
For full spec numbers, see Ace Combat 8 PC requirements.
Handhelds and Intel hardware
Respec tested the game on four PC handhelds (published Sep 25). On Steam Deck, it "keeps crashing when trying to play the campaign or even do the tutorial." The tester calls the instability on the Intel-based MSI Claw and OneXPlayer 3 "clearly an issue with Intel hardware at the moment".[9] Respec also says the game warned about D3D12 graphics driver issues on its AMD handhelds and on a PC with an AMD card.[9] If you are on one of these devices, a crash may not be something a setting can fix yet.
Black screen and "not loading"
We found no official statement that deals with black screens on their own. The steps above are the only ones with a named source. Respec notes that the game "compiles shaders on first boot", so a long first load is not by itself a crash.[9]
What we leave out
- Third-party "Error 01 patch" downloads. The official notices do not mention any downloadable fix.[1][2] We do not link to unofficial files.
- Forum workarounds. Player threads are useful for seeing which errors people hit, but we do not repeat untested tips as fixes.
- Anti-cheat workarounds. We do not cover them.
We will update this page when Bandai Namco posts a patch or an official explanation of Error 01.
Sources & References
- ACE COMBAT 8: WINGS OF THEVE on Steam: "Product Notice" (Sep 29, 2026) ↩ 1, 2, 3, 4, 5, 6, 7, 8
- ACE COMBAT 8: WINGS OF THEVE on Steam: "About Error Code: ST-3100001" (Sep 30, 2026) ↩ 1, 2, 3, 4
- ACE COMBAT 8: WINGS OF THEVE on Steam: "Flight Stick Support Update" (Sep 30, 2026) ↩
- Bandai Namco Entertainment America: "ACE COMBAT 8: WINGS OF THEVE Takes Flight Today" ↩
- Daniel Hidalgo, xboxplay.games: "How to Fix ACE COMBAT 8 Crashing Error 01" (Sep 30, 2026) ↩ 1, 2, 3
- ixbt.games: "Bandai Namco Apologizes for PC Version Issues of Ace Combat 8: Wings of Theve and Promises Prompt Fixes" (Sep 30, 2026) ↩
- ACE COMBAT 8: WINGS OF THEVE on Steam (system requirements section) ↩ 1, 2
- Daniel Hidalgo, xboxplay.games: "How to Fix ACE COMBAT 8 WINGS OF THEVE Not Launching" (Sep 30, 2026) ↩
- Mikhail Madnani and James Galizio, Respec: "Ace Combat 8 is too heavy for Steam Deck and ROG Ally, but there is hope for OneXPlayer3 and MSI Claw" (Sep 25, 2026) ↩ 1, 2, 3