Hello MuhammadShah-9129,
Thank you for posting in our Q&A forum.
In addition to set gpo, you will also configure offline files on clients by Sync Center manually.
Step 1. Go to Control Panel, switch its view to "Large icon" or "Small icons", then find Sync Center and click it to open.
Step 2. Click Manage offline files, then you will access the Offline Files window, it allows you to enable or disable offline files.
Step 3. To enable offline files, click Enable offline files under the General tab. After that, you will be asked to restart your computer, please do so.
Then we can set Computer Configuration > Administrator templates > Network > Offline Files > Scroll down the Offline Files Setting and double-click Allow or Disallow the use of Offline Files==> Enabled.
If it does not work above, please configure other gpo settings in this similar thread to see if it helps.
Hope the information above is helpful.
Best Regards,
Daisy Zhou
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