Hello and thanks for using Just Answer. I understand that you are having an issue with your OneDrive for Business syncing your folders and contents.
And your OneDrive is part of an Office 365 subscription correct?
Have you tried to disable the sync on that user and then enable it again? I had this happen to me a few days ago with my O365 enterprise subscription and had to work through it like this. Right click on the OneDrive for Business cloud icon in the task bar near the clock on the lower right side of your screen. You may need to expand using the small arrow for tha area. Once your right click the icon, select "stop syncing a folder..." and walk through the short wizard. Once you have done that you will want to log into the Office 365 and click on the cube of dots to open the menu on the top left side of the screen. Select OneDrive and when the screen opens select the "sync" option. This will start a new sync of your data that is located in the OneDrive cloud drive. Ensure you maintain network connectivity until the sync is complete. With that many files it may take quite awhile to sync them depending on your network throughput.
No phone call is needed. If you follow the steps above this should fix your issue and get your sync running again correctly to sync the file that are missing and getting ride of the hung operation you have going on.
Yes you would need to do that on the computer where you wish the files to be synced.
Also when you select the Sync option ensure that you are syncing in the same location as the original OneDrive for Business session. It will then compare the files and ensure the folders match the cloud copy without having to re-download existing files that are already located in that folder. Normally you would find the folder under C:\Users\%UserName%\OneDrive - %CompanyName% or possibly just C:\Users\%UserName%\OneDrive for Business
I hope my answer was the answer you were looking for to help you solve your problem. If it has worked for you and you are satisfied with my answer please let me know by rating my answer favorably. If you still require further assistance let me know and I would be happy to assist you further.
Thank you for using Just Answer. :)
You are very welcome and let me know if that was able to help you or reach back out to me if you have further need of assistance. :) Have a great day!!
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