How to Fix Microsoft Excel Not Working Properly in 2026

One of the most common reasons Microsoft Excel behaves erratically is a malfunctioning third-party add-in or extension. When you launch Excel normally, all installed add-ins load automatically in the background, which can occasionally trigger conflicts or memory leaks that cause freezes.

To check if an add-in is causing your issue, you should open Excel in Safe Mode, which disables all customizations and add-ins. Press the Windows key + R to open the Run dialog box, type excel /safe, and press Enter. If Excel opens smoothly and functions normally without crashing, navigate to File > Options > Add-ins. Select COM Add-ins from the drop-down menu, click Go, and uncheck your active add-ins one by one to identify the faulty culprit.

Core system files associated with Microsoft Office can occasionally become corrupted due to unexpected system shutdowns, failed background updates, or interference from third-party antivirus software. When these vital files break, Excel may fail to open entirely or crash upon loading specific workbooks.

Fortunately, Windows includes a built-in repair utility designed specifically for this situation. Close all open Office applications and open your system settings by navigating to Settings > Apps > Installed apps. Scroll down until you find your Microsoft 365 or Office installation, click the three-dot menu icon next to it, and select Modify. Choose Quick Repair first to scan and replace damaged files quickly. If the problem persists, return to the menu and select the more thorough Online Repair option, which performs a complete reinstallation while keeping your personal files intact.

Over time, accumulated temporary files, corrupted cache data, and rogue templates residing inside your Excel startup directories can prevent the application from initializing correctly. Clearing out these unnecessary files often resolves stubborn startup freezes and performance bottlenecks.

To clean your startup folder, open the Run dialog box using Windows + R and paste %appdata%\Microsoft\Excel\XLSTART to access the directory. Safely move any unexpected files or templates out of this folder to your desktop. Next, clear your system temporary files by searching for Disk Cleanup in your taskbar, selecting your primary drive, checking the box for temporary files, and clicking clean. Restart your computer before launching Excel again to ensure a clean cache state.

Modern versions of Microsoft Excel utilize your computer hardware graphics card to render visual elements smoothly. However, outdated graphics drivers or hardware incompatibilities can cause display glitches, lagging cells, and sudden application crashes when scrolling through large data sets.

If you can still open Excel, you can easily turn off this feature to test stability. Open a blank workbook and navigate to File > Options > Advanced. Scroll down to the Display section and check the box labeled Disable hardware graphics acceleration. Click OK to save your changes and restart the application. If your display performance improves immediately, consider updating your computer graphics card drivers through your system manufacturer or Windows Update.

Running an outdated version of Microsoft Excel leaves your software vulnerable to known bugs, unpatched memory leaks, and compatibility issues with newer operating system updates. Microsoft frequently releases cumulative patches and security updates that address stability issues reported by users worldwide.

To check for pending updates, open any Office application such as Word or Excel, and click on File > Account. Under the Product Information section, click the Update Options dropdown button and select Update Now. Allow the utility to check for, download, and install any available updates. Once the update process finishes, restart your device and verify whether Excel operates properly without any unexpected behavior.

If you have tried every troubleshooting step above and Microsoft Excel continues to malfunction, your installation files may be too severely corrupted for a standard repair utility. In this scenario, performing a clean uninstallation and reinstalling the software package is the most reliable path forward.

Go to your system control panel or Settings > Apps > Installed apps, locate Microsoft 365, and select Uninstall. To ensure all lingering registry keys and cache folders are completely removed, download the official Microsoft Office Uninstall Support Tool from the official support website and run it. After your system reboots, log into your Microsoft account portal, download the official installer package, and install a fresh copy of Excel onto your machine.