MS Project file opening in read only mode

Question

We had an MS Project file on SharePoint Online that is synced to the task list. Before I joined the company something happened (I realize it’s not helpful but nobody understands what happened) which caused the Project file to open always in read only mode. We cannot resave it or do anything else because an error keeps popping up that the file is read only.

I tried deleting all of the tasks from the SharePoint task list and to restore the Project file to a previous version before the problems started occuring, and try and resync it but it is still throwing the read only error when trying to sync.

Answer 1

There are several reasons why the file just open as read-only:

• Antivirus programs may open potentially unsafe files as read-only. Check with your antivirus provider to learn how to adjust these settings.
• If you have libraries with Checkout, Required, or Validation columns or metadata, or when Draft Item Security is set to either Only users who can edit or Only uses who can approve items in Version Settings of the library, these items will be synchronized as read-only. For more information, see the section "Libraries with specific columns or metadata" in the document Invalid file names and file types in OneDrive, OneDrive for Business, and SharePoint.

• An Office document opens in Protected View even though you enable the "Open Office documents as read/write while browsing" policy setting. For more information, see An Office document opens in Protected View even though you enable the "Open Office documents as read/write while browsing" policy setting.