MadEngineer:
After the update the onedrive app wouldn't sign into my microsoft account:
Microsoft OneDrive
You're syncing a different account
The account that you signed in with doesnt match the account that you're syncing.
Please provide the password for "".
To add another account, right-click the blue OneDrive cloud icon in the notification
area and click Settings. Click the Account tab, then click Add an account.
Sign in
(copy-pasted from elsewhere)
... and after uninstalling + reinstalling the app, the OneDrive folder in Explorer no longer links to my account, rather is local only in ~\OneDrive
Finally fixed this. Basically trashed both the onedrive and skydrive folders in my ~, killed the processes for the app and uninstalled it (in no particular order). Then ran the uninstall and reinstall as per https://answers.microsoft.com/en-us/onedrive/forum/odwork-odfiles/repair-onedrive-install-in-windows-10/37b6b966-2e15-4380-8875-06ffa39e4fdd and signed in.
This got the app going again but the icon was still wrong, fix for that here: https://answers.microsoft.com/en-us/onedrive/forum/odwork-odedit/onedrive-folder-icon-missing-in-fileexplorer/2cf2b9cb-733d-4218-bfff-49512fc50ef7. I was too impatient to wait for the icon to re-appear so performed a restart of explorer.exe from task manager.
Possibly caused by having onedrive for business installed on my PC as part of Office 2016 Pro? I'm not using that and there isn't an immediately obvious way of removing it but at least everything is working now