0.5.7.1 breaks cmd.exe in a strange way..

[sysdmp]

initially discovered while doing this https://github.com/ProbablyManuel/requiem/wiki/Installing-Requiem-with-Mod-Organizer-2

try adding C:\WINDOWS\system32\cmd.exe as an executable and run via MO2.

here's an exaple dir output compared to normal, notice how some filenames are cut off.
some are doubled and garbled.

normal (usvfs 0.5.7.0)

broken (usvfs 0.5.7.1)

CrediCredi is Credits.txt file
HeelsFix is HeelsFHeelsF

tab completion is also borked.
somehow this usvfs build affects CMD's file search/listing.
really weird stuff =)

tried on 2.5.3-beta2 and 2.5.2

ModOrganizer2/modorganizer#2217 (comment)
^ this build works fine though, stock 2.5.2 usvfs works fine as well of course except for win11 bug.

[Holt59]

What's the folder you're in (absolute path)? Can you upload a copy/paste of the working dir output? It'd be easier to reproduce locally.

[Holt59]

You can also try with this version of USVFS: https://github.com/ModOrganizer2/usvfs/releases/tag/v0.5.7.1 (extract the DLL and EXE from the bin folder into your MO2 folder).

Note that the USVFS version included in 2.5.3-beta.2 is not 0.5.7.1, it's something in-between 0.5.7.0 and 0.5.7.1...

[sysdmp]

What's the folder you're in (absolute path)? Can you upload a copy/paste of the working dir output? It'd be easier to reproduce locally.

D:\Modlists\VoidRim\root\Data
that's skyrimse copy inside mo2 instance, set up for wabbajack. I'm the author, not the user, so I'm setting this up and not using wj to install it.

You can also try with this version of USVFS: https://github.com/ModOrganizer2/usvfs/releases/tag/v0.5.7.1 (extract the DLL and EXE from the bin folder into your MO2 folder).

Note that the USVFS version included in 2.5.3-beta.2 is not 0.5.7.1, it's something in-between 0.5.7.0 and 0.5.7.1...

that IS the version that bugged out for me. exactly 4 files copied from bin folder to mo2 replacing files.
I tried copying it into MO2.5.2 and 2.5.3-beta.2 directories and could reproduce on both instances.

so far I tested 3 usvfs versions on 2 mo2 versions.

• stock 2.5.2 - works (except win11 GetModuleFileNameA issues)
• stock 2.5.3-beta.2 - works
• 2.5.2 + usvfs-0.5.7.1 - broken
• 2.5.3-beta.2 + usvfs-0.5.7.1 - broken
• 2.5.x + Silarn's build from thiscomment - works

I'll do some more testing and upload outputs as text with steps I took to reproduce.

[sysdmp]

ok here are the steps:

• create new portable instance with mo2

• replace files with usvfs-0.5.7.1

• add a mod, with some random files in it or install test mod provided below with dummy files.

• add a new executable C:\WINDOWS\system32\cmd.exe, open in skyrim data directory

• launch cmd.exe via mo2 exes, type dir, observe.

note, only files virtualized by usvfs are broken.
files natively in skyrim/data are fine.
in my previous output screenshot I installed CC files as mods so those are broken as well.

good output

D:\Steam\steamapps\common\Skyrim Special Edition\data>dir
 Volume in drive D is DATA
 Volume Serial Number is A223-6341

 Directory of D:\Steam\steamapps\common\Skyrim Special Edition\data

05/30/2025  11:28 AM    <DIR>          .
05/18/2025  10:56 AM    <DIR>          ..
05/18/2025  11:44 AM       249,753,412 Skyrim.esm
05/30/2025  11:27 AM                 0 0123456789.txt
05/30/2025  11:27 AM                 0 123456
05/30/2025  11:26 AM                 0 abcdef
05/30/2025  11:27 AM                 0 abcdefghijklmnopqrstuvwxyz.txt
05/30/2025  10:58 AM               105 meta.ini
               6 File(s)    249,753,517 bytes
               2 Dir(s)  2,253,057,949,696 bytes free

D:\Steam\steamapps\common\Skyrim Special Edition\data>

bad output

D:\Steam\steamapps\common\Skyrim Special Edition\data>dir
 Volume in drive D is DATA
 Volume Serial Number is A223-6341

 Directory of D:\Steam\steamapps\common\Skyrim Special Edition\data

05/30/2025  11:28 AM    <DIR>          .
05/18/2025  10:56 AM    <DIR>          ..
05/18/2025  11:44 AM       249,753,412 Skyrim.esm
05/30/2025  11:27 AM                 0 01234501234567
05/30/2025  11:27 AM                 0 123456
05/30/2025  11:26 AM                 0 abcdef
05/30/2025  11:27 AM                 0 abcdefabcdefghijklmnopqrstuvwx
05/30/2025  10:58 AM               105 meta.ime
               6 File(s)    249,753,517 bytes
               2 Dir(s)  2,253,059,432,448 bytes free

D:\Steam\steamapps\common\Skyrim Special Edition\data>

note that only abcdef and 123456 are not broken =)
Skyrim.esm is not broken because it's natively in data folder without going thru usvfs.

test mod.zip - this is the mod with those files.

[sysdmp]

total sting length is correct, but it wraps at 6 chars and starts again until reaches same string length.

it affects other apps launched via MO2 that work with paths, not only cmd.exe.

[Holt59]

Thanks, I can reproduce, I will try to investigate.

[Holt59]

@sysdmp #84 should fix this, you can test by yourself with the CI artifacts if you want.

[sysdmp]

@sysdmp #84 should fix this, you can test by yourself with the CI artifacts if you want.

indeed, seems fine.
thanks a lot for quick response!

05/30/2025  11:27 AM                 0 0123456789.txt
05/30/2025  11:27 AM                 0 123456
05/30/2025  11:26 AM                 0 abcdef
05/30/2025  11:27 AM                 0 abcdefghijklmnopqrstuvwxyz.txt
05/30/2025  10:58 AM               105 meta.ini

url if someone else want to test: https://github.com/ModOrganizer2/usvfs/actions/runs/15362302870/artifacts/3233580901