well that specific error is because it couldn't look up launcher.mojang.com. Is this computer connected to the internet (hopefully not thinking about it)? if not, the redistributable can't download the original launcher jar to patch it.

edit: also unrelated, where did you find a version of OpenJDK 21 that works on XP???

1. yes this computer is totally connected to internet, which can sound strange but isnt a real problem, i know what i download and my modem is firewalled, so i got no problems til this day
2. on onecoreapi github page said that you could install liberica jre without needing nothing, just install it and it works, i tried and it... worked- at least as far as i know (https://bell-sw.com/pages/downloads/#jdk-21-lts if you want the link)

hmm the fact that it couldn't look up the domain is strange then. What happens when you visit https://launcher.mojang.com/ in a browser? (it should show an XML error page)

if your browser can't look up the domain, it might be your system's DNS setup. If it can, maybe it's a java issue.

My computer is turned off right now, but i tried doing this earlier and it showed the xml page

okay, was the launcher error a one-time thing or does it happen every time you run the launcher? if there's a temporary outage while the launcher is opening, there will be issues like that.

Debugging this is hard because the issue is quite possibly upstream of any olauncher code

every time, but yea its very hard, i thought of just copying the files that olauncher creates on .minecraft, but my other pc is x64 so i think the created data is different? i dont know even if this would work, if you want me to perform some test i can do it here

Nope, java bytecode is java bytecode. It doesn't matter what platform it is compiled on. It should work if you copy over the autool directory.

i copied the autool directory, and now it opens, but now i got this error on the launcher when i try to login with the options

alright, that is because your JVM's truststore is out of date

3 things i discovered

1. the java was opening on java 8u45 (as you see i didnt opened it from console this time so it didnt used java 21) that came with the toshiba recovery cd when i formatted this notebook last time

2. i get strange errors with different versions of java, check it on the video (when i click ok button on the microsoft failed authentication it does the unhandled thing on java 17 and 11 i think its hard to know cause my cursor didnt appeared for some reason), (i cutted some parts of the video cause this computer is not so fast when recording so i had to cut some things and make others straight to the point, but i didnt cutted any part of the log or something like that, i just cutted the loadings that were mostly freezed screens)

3. java detects my pc as windows 7, which i dont know if its cause i installed onecoreapi? i not so sure, but im not using compatibility mode on java.exe neither i used when i installed it (its impossible cause its a .msi installer not exe)

over all:
java 21 crashes when click login
java 17 & 11 fails when authenticating

video: https://www.mediafire.com/file/j0j4eparrl7n0n4/Meu_Filme%7E1.mp4/file

I see a lot of "Connection timed out" so maybe there is an issue there. Also, use the device code option for logging in. It is way more likely to work.

Try java 8, I’ve had connectivity errors with java 9 on XP and Vista

here's a forum post that details the process of getting this working https://board.eclipse.cx/viewtopic.php?t=707