Steam OSS Crash when trying to use in PIE

Development Programming & Scripting Multiplayer & Networking
, ,
1

I have the Steam OnlineSubsystem working in packaged builds; I was hoping to enable it in PIE to be able to better debug issues. I found a console variable `OSS.SteamUnitTest` that seems to be able to circumvent the limitations of running Steam OSS in PIE. However, whenever I try running on PIE, it looks like the first OnlineTick() of the OSS causes the following crash:

`Exception thrown at 0x0000023CFC538CEE (steamclient64.dll) in UnrealEditor-Win64-DebugGame.exe: 0xC0000005: Access violation reading location 0x000000CFC2540000.`

From what I can see in the logs, it seems to be working fine up until that point:

```

[2026.01.09-23.45.13:845][ 0]LogSteamShared: Display: Loading Steam SDK 1.57

[2026.01.09-23.45.13:847][ 0]LogSteamShared: Steam SDK Loaded!

[2026.01.09-23.46.41:881][233]LogOnline: STEAM: Steam User is subscribed 1

[2026.01.09-23.46.41:881][233]LogOnline: STEAM: [AppId: XXXXXXX] Client API initialized 1

[2026.01.09-23.46.41:888][233]LogOnline: OSS: Created online subsystem instance for: STEAM

[2026.01.09-23.46.41:888][233]LogOnlineIdentity: STEAM: Obtained steam authticket

```

I understand that there are probably reasons around the existing safe guards of not using the steam OSS in editor/PIE but I was wondering if this is a known issue with any sort of workaround that would be safe for local debugging?

[Attachment Removed]

2

Steps to Reproduce

  1. Enable Steam OSS
  2. I add the following line in my game instance subsystem that interacts with the OSS to force Steam OSS to initialize: `GEngine->Exec(GetWorld(), TEXT(“OSS.SteamUnitTest 1”));`
  3. Run PIE and I hit the crash
    [Attachment Removed]
3

Hi there,

Steam OSS is typically not used in PIE due to some assumptions the Steamworks SDK makes about the running process. Additionally the Engine disables the drivers for Steam Sockets making Steam Networking unavailable. However it should be possible as there are third party tools that make it possible to at least initialise the system albeit without full functionality.

I would recommend using running in standalone instead of PIE & also enabling the Editor Setting “Run Under One Process”. As that is one of the assumptions made by the Steamworks SDK.

I would like to nail down where you are getting this exception. However I haven’t had any luck in reproducing it so far. Could you please provide some more detailed repro steps and/or a minimal repro project?

Cheers,

Louis

[Attachment Removed]

4

I have tried using standalone instead of PIE and can confirm I am not hitting the exception.

I will make some time to reproduce the exception and provide more specific steps or a repro project soon (hopefully in the next week or so)

[Attachment Removed]

5

That’s great. Thank you for letting me know, I’ll keep an eye out for your next correspondence.

- Louis

[Attachment Removed]