Solved: Excel Stuck on 'Opening file 0%' or 'Processing'

You double-click your crucial financial report. The green Excel logo appears. The status bar says "Opening file 0%". And you wait. And wait. It simply refuses to load, or the window goes white and says "(Not Responding)".

This is a legacy issue that has plagued Excel users from version 2013 up to Office 365. Here is how to unstick it.

Root Cause Analysis

Excel is trying to communicate with the OS or the printer driver to render the sheet, or an external plugin is blocking the main thread. Common culprits:

1. Hardware Graphics Acceleration: Excel tries to use your GPU to render cells. If the driver hangs, Excel hangs.
2. Corrupt Add-ins: A plugin (like a PDF converter or a Stock connector) is failing to initialize.
3. DDE (Dynamic Data Exchange): An old setting that tells Excel to ignore open requests from Windows Explorer.

The Solution: Step-by-Step

1. Disable Hardware Graphics Acceleration (Classic Fix)

Note: In newer Office 365 builds, this option has been moved or removed, but check if you have it.

1. Open Excel (a blank book).
2. Go to File > Options > Advanced.
3. Scroll down to the Display section.
4. Check "Disable hardware graphics acceleration".
5. Click OK and restart Excel.

2. The "Ignore DDE" Setting

If you can open Excel from the Start menu but NOT by double-clicking a file, this is the cause.

1. File > Options > Advanced.
2. Scroll to the General section (near the bottom).
3. Uncheck "Ignore other applications that use Dynamic Data Exchange (DDE)".
   • If it is already unchecked, leave it alone.
   • If checked, Excel ignores the "Open this file" command sent by Windows Explorer.

3. Open in Safe Mode

To confirm if an Add-in is the problem:

1. Hold the Ctrl key.
2. Click the Excel icon to launch it.
3. It will ask: "Do you want to start Excel in Safe Mode?" Click Yes.
4. Now try File > Open your document. If it opens instantly, you have a bad Add-in. Go to File > Options > Add-ins > COM Add-ins > Go and disable them one by one until you find the traitor.

Alternative Fix: Check Your Default Printer

Believe it or not, Excel queries your default printer to determine page breaks and layout before showing the data. If your default printer is a network printer that is offline or unreachable, Excel will hang until the request times out. Test: Set your default printer to "Microsoft Print to PDF" in Windows Settings. If Excel suddenly becomes fast, remove and reinstall your old printer driver.

Expert Tip: The Hidden "Personal.xlsb"

[!TIP] Corrupt Macro Workbook If Excel hangs even on a blank sheet, your personal macro workbook might be corrupted. Navigate to: C:\Users\<You>\AppData\Roaming\Microsoft\Excel\XLSTART If you see Personal.xlsb, move it to your Desktop (don't delete it yet). Restart Excel. If it works, that file was the issue. You can try to recover your macros from the moved file later.

Conclusion

Excel is a powerhouse, but it is fragile when it comes to drivers and plugins. 90% of "hanging" issues are resolved by disabling graphic acceleration or fixing the default printer.