If you are trying to open an online-only file in OneDrive and see the following error:
Couldn't start Files on Demand
Please restart your computer and try again. Error codes: <error code>
This may be because the Files on Demand service is being blocked from starting by legacy filters on some antivirus software. To address this issue, try the following:
Solution 1: Update and restart your computer
You should also ensure that OneDrive itself is updated to the latest version. Here's how:
On your desktop, select the OneDrive icon in the notification area.
Select Help & Settings , then in the pop-up menu, select Settings.
On the About tab, note the version number in the About Microsoft OneDrive section, then select the link.
On the OneDrive release notes page that opens, check that number against the latest release at the top of the page, and select Download OneDrive for Windows if the latest release is a higher number.
Solution 2: Update your antivirus software
Updating your antivirus software may update the filters that cause this issue. For more details, contact your software manufacturer.
Need more help?
For technical support, go to Contact Microsoft Support, enter your problem and select Get Help. If you still need help, select Contact Support to be routed to the best support option.