Hi, @Stefanos
For the first question, you can have a try of the following methods:
- Update to the latest Windows version.
Press "win+I" key to open the settings on the computer, then click Update & Security ->Windows Updates and click Check for updates. - Update OneDrive manually.
Go to the OneDrive website, click download and install the latest version of the application to the computer. - Reset OneDrive application.
Press the "Win+R" key simultaneously to open the Run dialog and enter %localappdata%\Microsoft\OneDrive\onedrive.exe/reset, click OK. Then sign in with your account information and
right-click the OneDrive icon in the taskbar, choose Settings. Under the settings tab, check the Start OneDrive automatically when I sign in to Windows then click OK. - Disable security features.
Go to Windows Security, click Virus & threat protection then find Manage settings. Then turn off the Real-time Protection. Then go to Windows Security, click Firewall & network protection and click Private network, then you can turn off the Windows Defender Firewall. - Remove all OneDrive entries from registry.
Press the "Win+R" key to open the Run diglog and type regedit. Go to the Edit tab then click Find. In the Find window, enter onedrive and make sure to check all Look at options, then click
Find next. After finding the OneDrive entry delete it and repeat the previous step.
And for the second question, we suggest you to share the parent folder. Then click the setting of child folder, choose manage access->advanced, then choose Manage Parent.
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