PSA: CK update uses a new BA2 archive format

[SKKmods]

This is like the .160 ESL header format all over again ... 

Mod authors who have updated their Fallout4.exe game to 1.10.980 are forced to update their CreationKit to 1.10.943.

CreationKit 1.10.943 uses a new BA2 archive file format which older versions of Fallout4.exe game can not open.

The new 1.10.980 Fallout4.exe can open the old and new BA2 archive format to use existing or new mods, so no problem if you have updated.

If you are not updating your Fallout4.exe for compatibility reasons, you may not be able to use new published mod versions UNLESS the author painstakingly packs the BA2 archive by hand using an old tool. This will significantly affect VR enjoyers (like the old 0.95 file header).

When publishing mods, be clear WHAT version of BA2 you are publishing, example:

(a) SKKSynthVision_002_980 Update 002 using the new BA2 archive format - use this if you have updated Fallout4.exe Apr 2024 1.10.980 

(b) SKKSynthVision_002_162 Update 002 using the old BA2 archive format - use this if you are stuck on Fallout4.exe Nov 2019 1.10.162

 

UPDATE: the BSArchPro utility packed with xEdit 4.1.5f will OPEN the new BA2 format and SAVE the old BA2 format, so workflow can be: Meak new format archive in Creation Kit, drag into BSArch and save old format BA2.  

 

What is INFURIATING is that I partipcate in several bethesda developer early adopter programmes and the first I knew of this is when I published a new mod created in CK .980 on  its release day and some users reported symptoms as if the scripts were missing. Turns out they had not updated Fallout4.exe and could not open the BA2 archives. Hence the hand packing and secondary file publication. GRRRRR.

[worm82075]

So the old BA2 format doesn't work with the new EXE?

[LarannKiar]

11 hours ago, worm82075 said:

So the old BA2 format doesn't work with the new EXE?

No, the post-update (v1.10.980) EXE can load archives saved with the pre-update Archive2 (v1.1.0.4).

The issue is that BA2s saved with the updated Archive2 (v1.1.0.5) can't be loaded by the pre-update (v1.10.163) EXE. It doesn't crash (based on a very few tests) but skips loading them.

I don't know if there's any performance difference between load times regarding the different archive formats, i.e. whether the post-update EXE loads archives saved with Archive2 v1.1.0.5 faster.

Edited April 27 by LarannKiar

[dizietemblesssma]

Did you mean 'pre-update Archive2(v1.1.0.4)'?

 

diziet

[LarannKiar]

5 hours ago, dizietemblesssma said:

Did you mean 'pre-update Archive2(v1.1.0.4)'?

 

diziet

Yes, edited my post.

[nzukowski]

Thank you for posting this.  

[SKKmods]

UPDATE: the BSArchPro utility packed with xEdit 4.1.5f will OPEN the new BA2 format and SAVE the old BA2 format, so workflow can be: Meak new format archive in Creation Kit, drag into BSArch and save old format BA2. Publish old format or both. Happy(er) days !

[PJMail]

And most annoying!? Some testing has shown that following the suggestion of using bsarch to re-save as v1 format, a binary comparison of this against the original v7/8 version has shown 1 byte difference... The version byte. Why Bethesda did you bother???

[DieFeM]

Whilst using Archive2.exe to pack a lot of new assets, which most never were packed before, I noticed it detects invalid texture formats, among other errors, so it processes the input files. I mean, it does not just pack them like zip or tar. So my guess is that the processing of the files is what has been updated, it probably performs tests that it didn't do before, so I think that this testing, by the output file, doesn't make any difference if the input was already processed, but the new version assumes that certain problems don't occur in an archive packed within this version.

[SKKmods]

EZ new 100% compatible BA2 workflow, no repacking required only a hex editor (I use Free Hex Editor Neo)