Mapped network drives are become a thing in the past with SharePoint Online as we now have the OneDrive for Business Sync Tool that can be used to sync files from SharePoint Online or OneDrive for Business. The sync client offers a seamless way to sync files from your devices and it just works.
If you are still using mapped network drives you may run into issues if your client PC is not configured correctly. Also, with SharePoint Online you will have to make sure to login and authenticate to SharePoint Online using a web browser and select Keep me signed in during login to make sure the mapped network drive stays authenticated.
Below are things to remember when using mapped network drives with SharePoint Online/OneDrive for Business:
- Make sure the WebClient service is set to start Automatically and not Manually in Service.msc (Start > Run > Services.msc)
- Make sure that all of your SharePoint Online and OneDrive for Business URL's are in the Trusted Sites list in Internet Explorer
- Browse to your SharePoint site and login and make sure to click Keep me signed in during login which will create a persistent cookie
- Attempt to map the network drive
If you reboot your PC you will need to make sure that:
- You open a web browser and navigate to your SharePoint Online site
- Make sure to click Keep me signed in check box to create a persistent cookie
Additional information can be found here which is a Microsoft support article.