PowerPoint files saved on the desktop will only reopen after previewing them first." Feel free to use either one for your Microsoft Community post.

Hi Jacsion,

I understand that you were told to perform windows inplace upgrade, but can you please confirm if how did you perform uninstall of your Office, is it just from the Control Panel? If yes, you may need to proceed with manually uninstalling your Office by following the steps on this link: https://support.microsoft.com/en-us/office/manually-uninstall-office-4e2904ea-25c8-4544-99ee-17696bb3027b

Try the following steps, in order, focusing on the fact that the issue only occurs for PowerPoint files on the desktop and that previewing them once makes them open normally:

1. Check if the file is blocked (common for files on Desktop or downloaded files)
   1. Open File Explorer.
   2. Go to the Desktop folder and locate one of the problematic .ppt/.pptx files.
   3. Right‑click the file and select Properties.
   4. In the General tab, look near the bottom for an Unblock checkbox or button.
   5. If Unblock is present, select it, then click Apply and OK.
   6. Try opening the file again by double‑clicking it.
   If this works, repeat for other affected files, or move them to a trusted folder where new files are not blocked.
2. Run a Quick Repair of Office (different from Online Repair you already tried)
   1. Select Start and type Control Panel, then open it.
   2. Go to Programs > Programs and Features.
   3. Select the installed Microsoft Office product and choose Change.
   4. Select Quick Repair, then Repair, and let it complete.
   5. Test by creating a new PowerPoint file directly on the desktop, then close and reopen it.
3. Re‑associate PowerPoint file types with PowerPoint
   1. Open Control Panel.
   2. Select Programs > Default Programs.
   3. Choose Set a default for a file type or link type.
   4. Enter .ppt and .pptx one at a time, and set PowerPoint as the default app for each.
   5. Select OK, then test opening a desktop PowerPoint file again.
4. If double‑click still fails, open from PowerPoint directly as a workaround
   1. Start PowerPoint first.
   2. Select File > Open, browse to Desktop, and open the file from there.

If none of these steps change the behavior, the most likely cause is a security or shell/preview integration issue specific to the Desktop folder. In that case, continue using a non‑Desktop folder (such as Documents or a dedicated presentations folder) for creating and saving PowerPoint files, as those locations are already working normally.

References:

• Error: Can't read file, or Presentation cannot be opened
• Double-clicking an Office file fails to open it in the correct Office program