I’m not very familiar with serialization in UE4, I don’t believe any of my code calls anything in those classes directly.
No other errors in the log. Last successfully packaged a month ago, reverting until then to see what’s causing it but no luck yet. I suspect it’s some corrupt blueprint somewhere…
Turns out I had a map referencing some now deleted files. Deleting the maps allowed packaging to finish with no issues. Was difficult to find the cause of the error since it was listed as a Warning, lots of those to sort through.
In my case, UE 5.3, I had split up the ALS anim map skeletal mesh into pieces using the model editing tool inside of the engine. This caused the mesh in my scene to segregate into a million pieces. I deleted a ton fo them out of my scene. I am pretty sure I hit save all also. Then, I closed my engine. The next day, when I tried to open the engine it crashed on open. So, looking at the log, I saw that it crashed while trying to reference anim man segments in a generated folder. So, I closed it down, went into the folder, and deleted all of the anim man segments out of that generated folder. When I started it back up, the engine loaded as normal.
Historically, for me, when the engine won’t start up, it has always been to some kind of corrupt mesh or other asset not being referenced properly. Perhaps, fixing redirectors in the generated folders before closing the engine is necessary? Maybe I didn’t hit save all? Anyway, that solved it for me.
Also, I saw the anim man stuff because I clicked the log in the error message and opened up the file in sublime text to see where it actually crashed.