Thanks Mia
Been through the microsoft remote troubleshooting, hosted via Quick Assist
case number 7050037519
case was escalated from Level 1 to Level 2
I was told by Microsoft Representative that this has nothing to do with windows update which, appears to me temporally preceeded the onenote syncing issue.
For me i have noticed in update history log: 2024-08 Cumulative Update Preview for Windows 11 Version 23H2 for x64-based Systems (KB5041587)
installed on 28th August, however not sure if this is the immediate culprit as there are a few microsoft defender updates around the same period. Syncing issue noticed first thing in the morning 29th Aug 2024.
The Level 1 tinkering by microsoft representative left the Office suite with error 29 universally, (this is issue of inability to log into office using my office 365 credentials, products was deemed unlicensed, syncing issue not solved)
This was then escalated to Level 2 which solved the error 29 but downgrading the Office to older version, however onenote syncing issue persisted.
The Level 2 representative suggested an ISO install as the ultimate fix that may fix 90% of issues, which, I attempted following the remote session.
However, same onenote syncing issue persisted (Error code: 0xE00009C8 bb0ur)
I was repeatedly informed that this is not a systemic issue, however i can see that 2 days into this thread there are already 10 people identified to have the same issue so far.
Still hoping for a solution from microsoft (the error essentially rendered my device useless without onenote).
Many thanks