Get multiple error codes - telling I have too little space (which was true, but have cleaned up and still not working) - and telling I don't meet the requirements. Your suggested program ran a check first that told I did meet the requirements, so this is also just bullsh*t.
And yes. I am sure I have 23h2. 100%. The suggested solutions on any pages does not work. I resign.
The Microsoft
"memory integrity system readiness scan tool 24h2"
Google it... found the drive which didn't meet the spec. That is hardly mentioned on the help sites. Found it after 9 weeks of going round the loop and reading the same old fixes. Just one driver that wasn't being used was causing the second boot to fail.
Found it being told to be used when I googled a fragment of the error log.
Basically Microsoft tightened up on security on this release so you have to pass a number of hurdles and those people that say its easy didn't have problem drivers, programs etc. I updated four PCs, one fully compliant W11 laptop no issue. Two non compliant tower units using the server method no issues. One fully compliant W11 laptop that through the raspberry for nine weeks.
Microsoft will have their work cut out to make this update work smoothly due to changing the rules for W11 enforcing better security. Their tools don't tell you what you need to do when it fails. Just vague suggestions unless you are a master with the log files.