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Fix Excel Add-in Error: Sorry We Can't Load the Add-in

Chanuka Geekiyanage Sep 27, 2026 869 views

Question details

The user is unable to load a third-party Excel add-in and needs a way to restore the add-in functionality.

How to Fix the 'Sorry, We Can't Load the Add-In' Error in Excel

Product: Microsoft Excel
Device & OS: not provided
Scenario: Opening Microsoft Excel to use a third-party extension, such as the Excel to SMS tool, for daily tasks.
Observed behavior: The add-in fails to load and displays the error message 'Sorry, we can't load the add-in', despite having an active internet connection.

Before you start

Verify that your internet connection is stable and try completely closing and restarting the Microsoft Excel application before modifying any advanced settings.

Solution 1Recommended

Contact the Add-in Provider for Support

Use this solution when dealing with a third-party add-in (like Excel to SMS), as the issue often lies with the provider's servers or authentication methods.

Because this specific issue typically involves compatibility, authentication, or service access limitations on the add-in provider's end, the most direct way to resolve it is to contact their support team.

Identify the add-in provider

Note the exact name of the add-in failing to load, such as Textlocal for the Excel to SMS feature.

Visit the official support page

Open your web browser and navigate to the official support or help desk website of the provider (e.g., https://www.textlocal.com/support).

Submit a support request

Open a ticket or use the live chat feature to report the 'Sorry, We Can't Load the Add-In' error, ensuring you mention your current Excel version.

Provider Updates: Providers frequently release patched versions of their add-ins to fix compatibility issues with the latest Microsoft Office updates.

Solution 2

Verify Add-in Status and Network Endpoints

Check your local Excel settings and network permissions to ensure the add-in is enabled and allowed to connect.

Solution 3

Update Microsoft Office

Install the latest Office updates to resolve internal bugs that might be preventing add-ins from loading correctly.

Free Microsoft Office alternative

Try WPS Office for a Seamless Spreadsheet Experience

If you are constantly dealing with complex add-in errors or heavy loading times in Microsoft Excel, consider switching to WPS Office. It is a highly compatible, lightweight, and free office suite that supports all standard spreadsheet formats with a familiar interface.

1. Download the software: Visit the official WPS Office website and download the free installation package.
2. Install WPS Office: Run the installer and follow the on-screen instructions to complete the setup in minutes.
3. Open your spreadsheets: Launch WPS Spreadsheets and open your existing .xlsx files directly to continue your work without interruptions.

Fully compatible with Microsoft Excel (.xlsx) file formatsLightweight design ensuring fast installation and quick app launchingRich set of built-in data analysis tools without relying heavily on third-party add-insFamiliar user interface that requires zero learning curve for Excel users

microsoft office alternative - wps office

Frequently Asked Questions

Why does my Excel add-in suddenly stop working?

Add-ins can stop working due to recent Office updates that introduce compatibility issues, expired authentication credentials with the provider, corrupted application cache files, or unexpected network connectivity problems blocking the add-in from reaching its server.

How do I clear the cache for Excel add-ins?

You can clear the Office add-in cache by navigating to the designated hidden folder on your system (typically located at C:\Users\<Username>\AppData\Local\Microsoft\Office\16.0\Wef), deleting the contents inside the folder, and then restarting Excel.

Can my firewall or antivirus block an Excel add-in from loading?

Yes, strict firewall rules or proactive antivirus software can block Excel from communicating with external servers. Third-party add-ins require specific network endpoints to function. If blocked, you may need to whitelist the add-in's domain in your security settings.

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