Hi ST8888,
From your post, I suppose you open the document by selecting a Word document name, clicking Open>Open in app in SharePoint online document library.
There are several reasons why a file may open as read only:
- Antivirus programs may open potentially unsafe files as read-only.
- 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.
Please check the following article to confirm this isn’t the case: SharePoint files open as read-only
In addition, try opening the document from Word 365 itself, see if the document still opens in Read Only. In Word, click File>Open>Browse, type the name of the site and select Document, as shown below:
Also, make sure you are sign into Office desktop apps with the same credentials which you used in SharePoint online to login.
If the issue persists, please conform the following information:
- As you mentioned other users can open file in desktop application without any issue, only you encounter the issue. May I know what permission do you have on site and library? Do you have the same permission as others?
- Does all the Word files in the library open in read-only? Please check if you can open Excel and PowerPoint files in desktop app.
- Please check if you have this issue opening files from other libraries in the same site and other sites.
- Could you please confirm whether you are using Monthly Channel or Semi-Annual Channel (Targeted)? You’ll find this information in any Office app, click File>Account, check under Product Information.
Thanks,
Neha