Security Policy Errors

How to Fix Excel XLOOKUP Add-In Blocked by Security Policies

John Wilson Oct 21, 2026 868 views

Question details

The user needs to understand why an XLOOKUP add-in is disabled in Excel and how to bypass the security restrictions to enable it.

How to Fix a Blocked Excel XLOOKUP Add-In

Product: Microsoft Excel
Device & OS: not provided
Scenario: Attempting to install or use a third-party XLOOKUP add-in to access the function in an older version of Excel.
Observed behavior: Excel actively blocks the add-in due to Trust Center security settings, administrator organizational policies, or an untrusted publisher.

Before you start

Verify the exact source of the XLOOKUP add-in to ensure it comes from a legitimate, trusted publisher before attempting to modify your security settings.

Solution 1Recommended

Modify Trust Center Settings to Allow Add-ins

Change your Excel Add-in security configurations to allow trusted publishers and unblock the necessary add-in.

Excel's default security settings often block third-party add-ins to protect your computer from malicious macros. By adjusting the Trust Center, you can permit specific add-ins to run safely.

Open Excel Options

Launch Microsoft Excel, click on the 'File' tab in the top-left corner, and select 'Options' at the bottom of the menu.

Navigate to the Trust Center

In the Excel Options window, click on 'Trust Center' in the left pane, then click the 'Trust Center Settings' button.

Adjust Add-in Security

Select 'Add-ins' from the left menu. Uncheck 'Require Application Add-ins to be signed by Trusted Publisher' if you are confident the add-in is safe, or uncheck 'Disable all Application Add-ins' if it is selected. Click 'OK' to save.

Modify Trust Center Settings to Allow Add-ins

Administrator Policies: If these options are grayed out, your organization's Microsoft 365 administrator has restricted these settings via Group Policy. You will need to contact your IT department to whitelist the add-in.

Solution 2

Unblock the Add-in File in Windows Properties

Remove the security block applied by Windows to downloaded add-in files.

Free Microsoft Office alternative

Use WPS Spreadsheet for Built-in XLOOKUP Support

Avoid complex add-in security blocks entirely by switching to WPS Office. WPS Spreadsheet natively supports advanced functions like XLOOKUP right out of the box, offering a seamless and secure experience without requiring third-party installations.

1. Download WPS Office: Visit the official WPS website to download and install the free WPS Office suite.
2. Open Your Spreadsheet: Launch WPS Spreadsheet and open your existing Excel workbook.
3. Use XLOOKUP Natively: Type '=XLOOKUP' in any cell to instantly use the function without needing to configure or unblock any add-ins.

Native support for XLOOKUP and advanced data analysis formulas.Fully compatible with Microsoft Excel formats (.xlsx, .xls, .csv).Free, lightweight, and completely free of third-party add-in security risks.Familiar user interface for a smooth transition from Microsoft Office.

microsoft office alternative - wps office

Frequently Asked Questions

Why does Excel automatically block my add-ins?

Excel blocks add-ins downloaded from the internet or from unverified publishers to protect your system from potentially harmful macros, scripts, or viruses.

Can I use XLOOKUP in older Excel versions without an add-in?

No. The XLOOKUP function is only available natively in Microsoft 365, Excel 2021, and newer versions. Older versions like Excel 2016 or 2019 require an add-in or an upgrade to support this function.

How do I add a publisher to my Trusted Publishers list?

When you open a file containing an add-in signed by a publisher, a security warning will appear in the message bar. Click 'Enable Content' or select 'Trust all from publisher' to automatically add them to your trusted list.

Microsoft Office Security Issues