I have an Office 365 for Business subscription and I'm using the Onedrive next generation sync client to sync libraries from sharepoint sub-sites to my PC. Everything was working fine until just over a week ago when the synchronisation stopped working after I rebooted my PC. On reboot, Onedrive reported a problem with my account and I was forced to re-login to the relevant account and then re-setup the sync for all the sharepoint sub-sites. Everything was then fine with just one exception - One sub-site which stubbornly refuses to sync any more.
Using the sharepoint sub-site library, I click on the "Sync" link at the top of the document library screen, a message appears saying "Getting ready to sync..." and then a dialog box appears asking "Open Microsoft OneDrive?". When I click on the "Open Microsoft OneDrive" button, OneDrive opens and immediately displays an error message saying "Sorry, OneDrive can't add your folder right now". Just below this message, it says "Please contact support." - See image below:
I have tried rebooting, removing and re-instating the account from OneDrive, resetting OneDrive, removing and re-installing the Onedrive next generation sync client software and all the associated accounts and waiting a week to see if this problem will go away and whatever I do, it does not solve the problem. No settings have been changed recently on this particular sub-site and all of my other sub-sites continue to sync correctly. I have also tried moving the target sync directory on the machine out of the way so that it could re-sync a complete fresh copy of all the files, but this does not work either. Whatever I do, I cannot get past the error screen above.
Please help - How do I get this sub-site to sync again? I have already tried the steps listed on the Microsoft troubleshooting page for the Next Generation Sync Client (Fix OneDrive Sync Problems ). Any other suggestions would be most welcome. The version of OneDrive I am using is "Version 2016 (Build 17.3.6799.0327)" (obtained from this link in the help article) on Windows 10 Professional.