Hi Nadia Madkour,
Welcome to Microsoft Q&A Forum! Have a good day and I hope you're doing well!
I totally get how frustrating it is when dragging or deleting folders looks like it worked, but nothing actually changes in Outlook desktop while Outlook on the web works fine. This usually points to a local cache or profile sync issue on the desktop app. Please try the steps below:
1. Create a new Outlook profile (to rule out corrupted profile/data)
- Close Outlook.
- Go to Control Panel > Mail (Microsoft Outlook) > Show Profiles > Add… > create a new profile and add your account.
- Set “Always use this profile” to the new one, then open Outlook and try again.
Microsoft guide: Create an Outlook profile - Microsoft Support
2. Repair or reset the Outlook/Office app
- Option A (Windows Settings): Search “Outlook” in Start > right‑click > App settings > Repair. If it still misbehaves, try Reset.
- Option B (Control Panel): Control Panel > Programs > Programs and Features > right‑click Microsoft 365 Apps > Change > choose Quick Repair. If that doesn’t help, try Online Repair.
Notes: Close all Office apps first. Online Repair needs internet and can take longer.
Microsoft guide: Repair an Office application - Microsoft Support
3. Rebuild the OST file (refresh the local cache)
- In Outlook: File > Account Settings > Account Settings > Data Files tab > select your account’s .ost file > Remove.
- Close Outlook, then go to:
%localappdata%\Microsoft\Outlook. Delete the related .ost file for your account. - Open Outlook again; it will create a fresh OST and re-sync everything from the server, including your custom folders.
Note: Only do this if your data is fully on the server. Confirm in Outlook on the web that all emails/folders are present. If you have any local-only data (e.g., items that haven’t synced, “This computer only” folders, or separate .pst files), back them up first.
I hope this information is at least partially helpful. Because things work on the web but not on desktop, this strongly suggests corrupted local cache/profile. The steps above will “refresh” Outlook locally without affecting server data. Please try them in order and let me know how it goes. If you have any concern or question, feel free to let me know. I’m here to help!
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