Excel Online is not working and won't open files

If Excel Online is not working and won’t open files, then read this post to solve the issue. Excel files often contain important organizational data or user information. These files can be opened and viewed using Excel Online, which is one of the best online spreadsheets software offered by Microsoft. Excel Online provides a collaborative platform where you can collectively work with others on the same spreadsheet. It makes it easier to create, edit, share Excel files, and access your Excel data from anywhere.

Excel Online is not working and won’t open files

Sometimes, Excel Online may not work as expected and won’t open files. In such cases, you may get error messages, such as ‘Couldn’t Open the Workbook‘, or ‘Request Was Taking Too Long‘.

Excel may fail to open your file if you or someone you’ve shared the file with has left it in idle mode for more than 6 hours, or if the file is too large or complicated to be handled by Excel Online. Wrongly configured workbook settings or browser issues may also cause the error to occur. This post discusses some effective troubleshooting tips that can help fix Excel Online if it is not working on your Windows 11/10 PC.

Make sure to close the file once you finish working on it. Also, encourage other users who have access to the file to close it as soon as they finish using them. This will reduce the chances of getting the error. Also, check the size of the file. If it is too large, split it into smaller files. If you still get the error, use these solutions to fix Excel Online is not working and won’t open files:

Clear browser cookies and cache.
Remove problematic add-ons.
Check the default file opening behavior.
Turn off Protected View.

Let us see these in detail.

1] Clear browser cookies and cache

Start by clearing your browser’s cookies and cache data. Each browser stores some information from the websites you visit in form of cookies and cache. This information is used to make it easier for you to return to the website. It also personalizes your browsing experience. When this data gets corrupted, it causes issues to the browser. Whether you are using Chrome, Edge, or Firefox, clearing cookies and cache can potentially fix the problem. However, for this particular issue, we recommend clearing cookies, site data, and cache only for Excel Online.

2] Remove problematic add-ons

Go to your browser’s plugins/add-ons/extensions page and look for any recently-installed add-ons that may be causing the issue. Temporarily disable add-ons one by one and see if it works for you. You may also reset your browser settings to restore it to its original state (when it was installed). This will help in case any problematic add-on or theme changed your browser settings without your knowledge. Resetting the browser will also change cookies and site data to default and possibly fix the ‘Excel Online not working and won’t open files’ issue.

3] Check the default file opening behavior

Excel files shared on Microsoft Teams are hosted on SharePoint Online. If you use Teams for group communications and Excel Online for collaborative work within your organization, check the default file opening behavior of documents in SharePoint’s Document Library. By default, it is set to ‘Open in the browser‘. Other available options are ‘Open in client application’ (i.e. Excel for Desktop), and ‘Use the server default’. If someone else has changed this setting, you may need to revert to the default settings to open the file in the browser.

4] Turn off Protected View

Some files may either be protected by the owner to prevent accidental changes by other users. If you’re not able to open the file, try downloading it on your Windows 11/10 PC. If the download is successful, open the file in your Excel desktop app. Then follow these steps to disable the protected mode:

Go to File > More… > Options.
Click on Trust Center on the left panel.
Then click on Trust Center Settings on the right panel.
In the next window that appears, click on Protected View on the left panel.
Uncheck all options listed under ‘Protected View’.
Click on the OK button

Once you turn off the protected view, save the file, and upload it to SharePoint Document Library. Try opening the file and see if it fixes the issue.

Apart from this, you can also try opening the file using other similar applications, such as Google Spreadsheets. Hope you find this useful.