So basically all that happened was that I logged off, and the next day I tried to load my singleplayer world and it crashed at the loading screen (it froze then windows gave me the option to close the program or wait) and I was given an exit code of:
"-805306369"
It told me there wasn't enough memory allocated to my launcher, but nothing seemed to work.

The full bug report is below:
https://pastebin.com/Ne2gygm8

Edited August 2, 20223 yr by jerryhamood
more info added

Unsupported version xD.

Edited August 2, 20223 yr by Luis_ST

This hasn't worked, and for some reason minecraft won't send the crash report even though it says so in the log. Any fixes for that?

 

If you've seen this and are also struggling with this problem, I found the answer here:
https://github.com/FTBTeam/FTB-Modpack-Issues/issues/364

1: You remove the files in 'serverconfig' folder (in your world folder),

2: Put the file(s) from the 'defaultconfigs' folder in the 'serverconfig' folder, which is located in your .minecraft folder.

(you should probably make a backup if that doesn't work btw)