[Bug] Steam not launching at all after install

[Dathuss]

Before Reporting

• I found no existing issues matching my bug
• My issue is not caused by a theme
• My issue is not caused by a plugin

Describe the Bug

Hello ! I just installed Millennium (latest, 2.17.2) for the first time on my Windows 10 22H2 and unfortunately i can't seem to launch steam at all.
The 'updating steam' popup shows as usual but then nothing else happens. I tried using both manual and automatic installations several times and nothing changes. The logs (systemmanager.txt) do show something though:

[2025-03-12 00:41:50] Client version: 1741636428
[2025-03-12 00:41:50] Initializing System Manager
[2025-03-12 00:41:50] Error: CSystemManager::CSystemManager: failed to load user32, some functionality may be disabled
[2025-03-12 00:41:50] Night mode active on resume 0
[2025-03-12 00:41:50] Initialized battery manager with query mode: 1 interval: 2000000
[2025-03-12 00:41:50] wifi power management: 1
[2025-03-12 00:41:50] Fan control available: 0 current: 0

apart from that, there's practically nothing popping up in any other log, as if it crashed very early. Launching without internet access changes nothing.
I don't really know what i can say anymore so feel free to ask anything, i'll do whatever i can to help. Thanks for your time

Expected Behavior

It should at least launch steam

Steps To Reproduce

That's the thing, I don't know. There's no antivirus on my system (apart from windows defender) and no kernel anti-cheat either.

Operating System

Windows

Anything else?

No response

[shdwmtr]

Start Steam with -dev parameter, check the console for more information.

[GSecurity]

EDIT: Found out the issue was related to Steam... and Adguard Desktop with specific advanced settings.
(To make is simple, the latest march update of Steam enforce controls of other apps interacting on the system and Steam - what did make steam crash at start. If Adguard Desktop has filtering of localhost traffic enabled in advanced settings, this will mess up with Steam and make it crash/stop. This was also the issue with Millenium even with the January version of Steam that was working. So basically, do not enable localhost filtering in Adguard Desktop advanced settings ^^)
Now it is working fine, problem solved on my side.

I have almost the same issue, first time installing.
My steam is launching fine, but Millennium is not with same error as OP in systemmanager.txt.
So only difference is that my steam is launching correctly anyway. (hope it is still right place to post).
This is what the console gives at the end:

[35:38.093] CORE Server started on ws://localhost:9123
[36:23.461] WARN (Steam-Error) [45.398] Failed to load apps with timelines Transport SendMsg: socket not ready
Info: (This warning may be non-fatal)
Where: (https://steamloopback.host/chunk~2dcc5aaf7.js?contenthash=2b0b41bbd07ac8a0b106:1:4298693)
[36:23.461] WARN (Steam-Error) SteamApp Init - After Login - Stage 2 - GRS - ERROR Transport SendMsg: socket not ready
Info: (This warning may be non-fatal)
Where: (https://steamloopback.host/chunk~2dcc5aaf7.js?contenthash=2b0b41bbd07ac8a0b106:1:4298607)
[36:28.400] CORE Using default accent color
[44:34.853] WARN Failed to emit message. exception: bad_function_call
[44:34.860] WARN Failed to emit message. exception: bad_function_call
[44:36.130] CORE Using default accent color

(Using steam build from January as the latest from yesterday (11 march 2025 re-release) has a critical bug that prevent steam to launch and crashes at launch for some people (ticket with steam ongoing) - but dont' think it changes anything with this issue, but saying just in case).

Edit: Adding full log screenshot just in case.

[Dathuss]

Start Steam with -dev parameter, check the console for more information.

Hey, thanks
So i tried launching steam as you said and i have a bunch of additionnal stuff
First an additional window popped belonging to your framework that seems to attest it loaded successfully

However, nothing more interesting shows up in the logs. But some crash dumps have been generated that provide a bit more info. They all come from steamwebhelper.exe and are all assertion fails. Either two dumps are generated or a single one.
In the first case, here are the two assertions raised:

Assert( bufRet.TellPut() == sizeof(uint8) ):C:\buildworker\steam_rel_client_win64\build\src\clientdll\steamclient.cpp:836
Assert( CClientPipe::BWriteAndReadResult: BWrite failed ):C:\buildworker\steam_rel_client_win64\build\src\common\pipes.cpp:863

000000e0`2792f8d0 00007ff6`b9941543     : 00000000`00000000 00000000`00000000 00000000`00003fb4 00000256`b1113f20 : steamwebhelper!CreateInterface+0x2483d
000000e0`2792f900 00007ff6`b99c5c24     : 00007ff6`b9e231f0 00007ff6`b9947c50 00000000`00000000 000000e0`2792f990 : steamwebhelper!GetHandleVerifier+0x123813
000000e0`2792f980 00007ff6`b99c7bcc     : 00007ff6`b9e231f0 00000000`0000001a 00000256`b11490e0 000000e0`2792faa0 : steamwebhelper!GetHandleVerifier+0x1a7ef4
000000e0`2792fa50 00007ff6`b9b3bc0a     : 00000000`0000000a 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!GetHandleVerifier+0x1a9e9c
000000e0`2792fc20 00007ffd`cccc7344     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!CreateInterface+0xb0bba
000000e0`2792fc60 00007ffd`cd9826b1     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : kernel32!BaseThreadInitThunk+0x14
000000e0`2792fc90 00000000`00000000     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : ntdll!RtlUserThreadStart+0x21

Both their stack traces are the same. In the case only one dump is generated, here's the assertion:

Assert( Assertion Failed: Illegal termination of worker thread 'CGamepadAPITask::Run' ):C:\buildworker\steam_rel_client_win64\build\src\tier0\threadtools.cpp:3601

00000044`2fb9e6e0 00007ffd`5cf675bc     : 0000014a`e86210e0 00007ffd`5cf67460 0000014a`e86210e0 00000000`00000000 : crashhandler64!CreateInterface+0x497b7
00000044`2fb9e720 00007ff6`b9abc96a     : 00007ffd`5cfcb0b8 00000044`2fb9e860 00007ffd`5cfb3cb8 00000000`00000000 : crashhandler64!CreateInterface+0x243c
00000044`2fb9e760 00007ff6`b9abcd57     : 00000000`00000000 00007ff6`b9cf6b50 00000000`00000e11 00000000`00000000 : steamwebhelper!CreateInterface+0x3191a
00000044`2fb9f1a0 00007ff6`b9ab8dc3     : 0000014a`e6ea2be0 00000000`00000000 00000000`00000000 00007ff6`b9cb1e7c : steamwebhelper!CreateInterface+0x31d07
00000044`2fb9f1d0 00007ff6`b9ab8ef7     : 00000044`2fb9f352 00007ff6`b9cf6db0 00000044`2fb9f5a8 00000000`00000000 : steamwebhelper!CreateInterface+0x2dd73
00000044`2fb9f310 00007ff6`b9ab8998     : 00007ff6`b9e23538 0000014a`e51659a8 00000000`00000000 00000000`00000001 : steamwebhelper!CreateInterface+0x2dea7
00000044`2fb9f560 00007ff6`b9aaf4e8     : 0000014a`e519c6a0 00007ff6`00000000 00007ff6`b9cf6db0 00007ff6`b9e23550 : steamwebhelper!CreateInterface+0x2d948
00000044`2fb9f590 00007ff6`b99343e1     : 00007ff6`b9e23538 00000044`2fb9f6c0 0000014a`e5165970 0000014a`e51659a8 : steamwebhelper!CreateInterface+0x24498
00000044`2fb9f5d0 00007ff6`b9b61781     : 00007ff6`b9e231f0 00007ff6`b9e23538 00007ff6`b9e23618 00007ff6`b9e235d0 : steamwebhelper!GetHandleVerifier+0x1166b1
00000044`2fb9f630 00007ff6`b9b61525     : 00000044`2fb9f6f0 00000044`2fb9f7a0 00000000`00000000 00000044`2fb9f750 : steamwebhelper!CreateInterface+0xd6731
00000044`2fb9f670 00007ff6`b9b61859     : 00000044`2fb9f788 00000044`00000003 00000044`2fb9f738 00000044`2fb9f6f0 : steamwebhelper!CreateInterface+0xd64d5
00000044`2fb9f6a0 00007ff6`b9b49179     : 00007ff6`b9faca48 00000000`00000000 00000000`00000002 00000000`00000002 : steamwebhelper!CreateInterface+0xd6809
00000044`2fb9f6e0 00007ff6`b9b490ed     : 00000000`00000004 00007ff6`b9b6e6e4 00000000`00000022 00000000`00000000 : steamwebhelper!CreateInterface+0xbe129
00000044`2fb9f720 00007ff6`b9b49277     : 00000000`00000000 00000000`00000000 0000014a`e513f240 00000044`2fb9f774 : steamwebhelper!CreateInterface+0xbe09d
00000044`2fb9f750 00007ff6`b9b3bc6c     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!CreateInterface+0xbe227
00000044`2fb9f7b0 00007ffd`cccc7344     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!CreateInterface+0xb0c1c
00000044`2fb9f7f0 00007ffd`cd9826b1     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : kernel32!BaseThreadInitThunk+0x14
00000044`2fb9f820 00000000`00000000     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : ntdll!RtlUserThreadStart+0x21

I'd be glad to share the dump files, however not in public. Thanks for your time.

[GSecurity]

Start Steam with -dev parameter, check the console for more information.

Hey, thanks So i tried launching steam as you said and i have a bunch of additionnal stuff First an additional window popped belonging to your framework that seems to attest it loaded successfully

However, nothing more interesting shows up in the logs. But some crash dumps have been generated that provide a bit more info. They all come from steamwebhelper.exe and are all assertion fails. Either two dumps are generated or a single one. In the first case, here are the two assertions raised:

Assert( bufRet.TellPut() == sizeof(uint8) ):C:\buildworker\steam_rel_client_win64\build\src\clientdll\steamclient.cpp:836
Assert( CClientPipe::BWriteAndReadResult: BWrite failed ):C:\buildworker\steam_rel_client_win64\build\src\common\pipes.cpp:863

000000e0`2792f8d0 00007ff6`b9941543     : 00000000`00000000 00000000`00000000 00000000`00003fb4 00000256`b1113f20 : steamwebhelper!CreateInterface+0x2483d
000000e0`2792f900 00007ff6`b99c5c24     : 00007ff6`b9e231f0 00007ff6`b9947c50 00000000`00000000 000000e0`2792f990 : steamwebhelper!GetHandleVerifier+0x123813
000000e0`2792f980 00007ff6`b99c7bcc     : 00007ff6`b9e231f0 00000000`0000001a 00000256`b11490e0 000000e0`2792faa0 : steamwebhelper!GetHandleVerifier+0x1a7ef4
000000e0`2792fa50 00007ff6`b9b3bc0a     : 00000000`0000000a 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!GetHandleVerifier+0x1a9e9c
000000e0`2792fc20 00007ffd`cccc7344     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!CreateInterface+0xb0bba
000000e0`2792fc60 00007ffd`cd9826b1     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : kernel32!BaseThreadInitThunk+0x14
000000e0`2792fc90 00000000`00000000     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : ntdll!RtlUserThreadStart+0x21

Both their stack traces are the same. In the case only one dump is generated, here's the assertion:

Assert( Assertion Failed: Illegal termination of worker thread 'CGamepadAPITask::Run' ):C:\buildworker\steam_rel_client_win64\build\src\tier0\threadtools.cpp:3601

00000044`2fb9e6e0 00007ffd`5cf675bc     : 0000014a`e86210e0 00007ffd`5cf67460 0000014a`e86210e0 00000000`00000000 : crashhandler64!CreateInterface+0x497b7
00000044`2fb9e720 00007ff6`b9abc96a     : 00007ffd`5cfcb0b8 00000044`2fb9e860 00007ffd`5cfb3cb8 00000000`00000000 : crashhandler64!CreateInterface+0x243c
00000044`2fb9e760 00007ff6`b9abcd57     : 00000000`00000000 00007ff6`b9cf6b50 00000000`00000e11 00000000`00000000 : steamwebhelper!CreateInterface+0x3191a
00000044`2fb9f1a0 00007ff6`b9ab8dc3     : 0000014a`e6ea2be0 00000000`00000000 00000000`00000000 00007ff6`b9cb1e7c : steamwebhelper!CreateInterface+0x31d07
00000044`2fb9f1d0 00007ff6`b9ab8ef7     : 00000044`2fb9f352 00007ff6`b9cf6db0 00000044`2fb9f5a8 00000000`00000000 : steamwebhelper!CreateInterface+0x2dd73
00000044`2fb9f310 00007ff6`b9ab8998     : 00007ff6`b9e23538 0000014a`e51659a8 00000000`00000000 00000000`00000001 : steamwebhelper!CreateInterface+0x2dea7
00000044`2fb9f560 00007ff6`b9aaf4e8     : 0000014a`e519c6a0 00007ff6`00000000 00007ff6`b9cf6db0 00007ff6`b9e23550 : steamwebhelper!CreateInterface+0x2d948
00000044`2fb9f590 00007ff6`b99343e1     : 00007ff6`b9e23538 00000044`2fb9f6c0 0000014a`e5165970 0000014a`e51659a8 : steamwebhelper!CreateInterface+0x24498
00000044`2fb9f5d0 00007ff6`b9b61781     : 00007ff6`b9e231f0 00007ff6`b9e23538 00007ff6`b9e23618 00007ff6`b9e235d0 : steamwebhelper!GetHandleVerifier+0x1166b1
00000044`2fb9f630 00007ff6`b9b61525     : 00000044`2fb9f6f0 00000044`2fb9f7a0 00000000`00000000 00000044`2fb9f750 : steamwebhelper!CreateInterface+0xd6731
00000044`2fb9f670 00007ff6`b9b61859     : 00000044`2fb9f788 00000044`00000003 00000044`2fb9f738 00000044`2fb9f6f0 : steamwebhelper!CreateInterface+0xd64d5
00000044`2fb9f6a0 00007ff6`b9b49179     : 00007ff6`b9faca48 00000000`00000000 00000000`00000002 00000000`00000002 : steamwebhelper!CreateInterface+0xd6809
00000044`2fb9f6e0 00007ff6`b9b490ed     : 00000000`00000004 00007ff6`b9b6e6e4 00000000`00000022 00000000`00000000 : steamwebhelper!CreateInterface+0xbe129
00000044`2fb9f720 00007ff6`b9b49277     : 00000000`00000000 00000000`00000000 0000014a`e513f240 00000044`2fb9f774 : steamwebhelper!CreateInterface+0xbe09d
00000044`2fb9f750 00007ff6`b9b3bc6c     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!CreateInterface+0xbe227
00000044`2fb9f7b0 00007ffd`cccc7344     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : steamwebhelper!CreateInterface+0xb0c1c
00000044`2fb9f7f0 00007ffd`cd9826b1     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : kernel32!BaseThreadInitThunk+0x14
00000044`2fb9f820 00000000`00000000     : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : ntdll!RtlUserThreadStart+0x21

I'd be glad to share the dump files, however not in public. Thanks for your time.

Just to be sure, if you uninstall Millennium does steam work?
As I said in my post, the last update of steam has an issue for some people that makes it crash at start (and it seems related to steamwebhelper).
Asking just to be sure for devs :)

[Dathuss]

Just to be sure, if you uninstall Millennium does steam work? As I said in my post, the last update of steam has an issue for some people that makes it crash at start (and it seems related to steamwebhelper). Asking just to be sure for devs :)

Works like a charm. Only doesn't when millennium is installed. Tried both in steam release and beta. I don't think we have the same issue.

[GSecurity]

EDIT: updated my first answer with resolution of the issue on my side.

Just to be sure, if you uninstall Millennium does steam work? As I said in my post, the last update of steam has an issue for some people that makes it crash at start (and it seems related to steamwebhelper). Asking just to be sure for devs :)

Works like a charm. Only doesn't when millennium is installed. Tried both in steam release and beta. I don't think we have the same issue.

Hmm could be, I'll let devs remove my post in a separate topic if needed ^^
Thx for confirming though.

[shdwmtr]

Both of you should try the latest pre-release build. Download and extract it to the root of your steam folder overwriting existing files.

[Dathuss]

Both of you should try the latest pre-release build. Download and extract it to the root of your steam folder overwriting existing files.

Hi, thanks for the update. Unfortunately it didnt seem to fix my problem and as far as i can tell, nothing seems to have changed. Same logs, crashing right after the updating steam popup and same assert dumps. The Millennium logs seem to go for a bit longer though (see for yourself), but still no clear error

Standard Output_log.log
debug.log
pipx_log.log

[Dathuss]

@shdwmtr hey hey im back with an update

So i tried building millenium manually to see if i could... do stuff i'm not really sure what i was aiming for.
So i had built everything and millenium finally seemed to launch. I was a bit puzzled so i tried multiple different combinations of files and folders from your release zip and my build (set to Release mode) and i noticed that millennium only launches when i used my own compiled python311.dll.
I compiled it just like the README, only skipping Update Build Configuration to be MultiThreaded since i had MSBuild errors with the updated vcxproj file (i still use vs 2019 (the MSBuild version is 16.11.2.50704) so that's probably the reason why). Do what you want with all that but i think there's something wrong in your Python311.dll build session that somehow causes steam to crash on some computers

[Mr54233]

Same here, Steam won't start properly. I can see the icon in the status bar, but clicking it does nothing, and no window appears. After a while, a window pops up asking to restart Steam or similar options, but restarting doesn't help.

[Dathuss]

Same here, Steam won't start properly. I can see the icon in the status bar, but clicking it does nothing, and no window appears. After a while, a window pops up asking to restart Steam or similar options, but restarting doesn't help.

hi, this doesn't look like the same issue, open a new one and make sure to launch steam.exe with the -dev flag to try and pinpoint the issue

[Dathuss]

in the meantime hi @shdwmtr perhaps you have forgotten to respond

[shdwmtr]

@Dathuss I find it weird you can only get it to work with a manually compiled Python dll as the logs seem to show python successfully loaded (Anything written with blue text is being ran under Millenniums python plugin virtual environment).

Is there anything notable about your system? Ex. are you on an ARM based CPU etc.