I cant open some files

Run a full Online Repair of Microsoft 365 or Office because the screenshot shows PowerPoint itself failing during startup, rather than an error identifying one particular presentation.

Repair PowerPoint on Windows 11

1. Close PowerPoint and all other Office applications.
2. Right-click Start → Installed apps.
3. Find Microsoft 365 or Microsoft Office.
4. Select the three dots (…) → Modify.
5. If shown How would you like to repair your Microsoft 365 and Office programs?, choose Online Repair → Repair.
   • If yours is an MSI-based Office installation, choose Repair → Continue instead.
6. Complete the repair, restart Windows if requested, and then open PowerPoint without selecting a presentation.

Online Repair is more thorough than the Repair Now button in the error dialog or Quick Repair, and it repairs the whole Office suite even when only PowerPoint is affected.^1^

If Online Repair does not fix it

Test PowerPoint without add-ins:

1. Press Windows key + R.
2. Enter:

powerpnt.exe /safe

3. Select OK.
4. If PowerPoint opens in Safe Mode, go to File → Options → Add-ins.
5. Beside Manage, select COM Add-ins → Go.
6. Clear all checkboxes and restart PowerPoint normally.
7. If it now works, re-enable add-ins one at a time, restarting PowerPoint after each one, to identify the conflicting add-in.^2^

If PowerPoint opens but only some presentations fail

That points to a problem with those files rather than the PowerPoint installation. Try recovering each affected file:

1. Open PowerPoint to a blank presentation.
2. Select File → Open → Browse. Do not select the file from Recent.
3. Select the affected presentation once.
4. Select the arrow beside Open → Open and Repair.^3^
5. If it opens, immediately save a new copy under a different filename.

If PowerPoint instead reports “Can’t read file” or “Presentation cannot be opened,” right-click the file in File Explorer → Properties. If an Unblock option appears, select Unblock → Apply → OK, and try opening it again.^4^

If Online Repair fails and PowerPoint also crashes in Safe Mode before opening a blank presentation, the next step is to uninstall and reinstall Microsoft 365/Office. Before uninstalling, confirm that the license or subscription is associated with the Microsoft account used to install Office.

References

1. Repair an Office application
2. PowerPoint isn't responding, hangs or freezes | Microsoft Support
3. Open a document after a file corruption error | Microsoft Support
4. Error: Can't read file, or Presentation cannot be opened | Microsoft Support