Security Policy Errors

How to Resolve Microsoft Security Warning for Office Files

Huda Qurayshi Oct 9, 2026 871 views

Question details

Users need to resolve a security warning that appears when attempting to open Microsoft Office files, typically associated with SharePoint access and Microsoft advisory SP861520.

How to Resolve Microsoft Security Warning for Office Files

Product: Microsoft Office
Device & OS: Windows
Scenario: Opening Office files hosted on an organizational SharePoint or network location.
Observed behavior: Office displays a message stating 'This content presents a potential security issue', and in some cases, applications like PowerPoint fail to open entirely.

Before you start

Ensure you have the exact URL of your organization's SharePoint site (e.g., https://yourcompany.sharepoint.com) and possess administrative privileges to modify Internet Options on your Windows device.

Solution 1Recommended

Manually Add SharePoint URL to Trusted Sites

This is the primary workaround for Microsoft advisory SP861520 and resolves the issue for individual affected devices.

Adding your company's SharePoint URL to the Trusted Sites list in Windows allows Microsoft Office applications to bypass the security block for files originating from that specific domain.

Open Internet Options

Click the Start menu, type 'Control Panel', and open it. Navigate to 'Network and Internet' and then click on 'Internet Options'.

Navigate to the Security Tab

In the Internet Properties window, click on the 'Security' tab at the top. Select the 'Trusted Sites' icon (the green checkmark) and click the 'Sites' button.

Add the SharePoint URL

In the 'Add this website to the zone' field, type your organization's exact SharePoint URL (e.g., https://yourcompany.sharepoint.com). Click 'Add', then close the dialog and click 'OK' to apply the changes.

Restart Office Applications

Close any open Microsoft Office applications, such as Word or PowerPoint, and attempt to open the SharePoint file again to verify the warning is gone.

Manually Add SharePoint URL to Trusted Sites

URL Verification: Ensure you type the 'https://' prefix when adding the site. Unsecured HTTP sites cannot be added unless you uncheck 'Require server verification'.

Solution 2

Deploy Trusted Sites Configuration via Microsoft Intune

Use this solution if you are an IT administrator needing to resolve the security warning across multiple organizational devices at once.

Free Microsoft Office alternative

Try WPS Office for a Hassle-Free Document Experience

If you are consistently blocked by Microsoft Office security policy errors or experiencing file application crashes, consider switching to WPS Office. It provides a lightweight, secure, and highly compatible alternative for handling your daily document tasks without unnecessary friction.

1. Download the Installer: Visit the official WPS Office website and click the free download button for your operating system.
2. Install the Application: Run the downloaded installer file and follow the simple on-screen instructions to set up the software.
3. Open Your Files: Launch WPS Office and directly open your existing Word, Excel, or PowerPoint documents to continue working immediately.

Highly compatible with Microsoft Word, Excel, and PowerPoint file formats (.docx, .xlsx, .pptx)Lightweight design ensures fast loading times, even on older devicesFamiliar user interface makes migration seamless with zero learning curveBuilt-in robust security features to protect your local and cloud documents

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Frequently Asked Questions

Why am I getting a 'potential security issue' warning in Microsoft Office?

This warning, often associated with Microsoft advisory SP861520, occurs when Microsoft Office applications cannot definitively verify the safety of a network location or SharePoint site, triggering a built-in security block to protect your device.

Is it safe to add my company's SharePoint to Trusted Sites?

Yes, as long as the URL belongs to your organization's official SharePoint or a verified, secure corporate network. Adding an official corporate site simply tells Windows that files from this source are safe to open.

Why does PowerPoint completely fail to open after the warning?

Extremely strict organizational security policies or a software glitch triggered by the security block may prevent the application from launching entirely. Temporarily downloading the file locally to your desktop before opening it may bypass this issue.

Can I disable this security protection globally in Office?

It is highly discouraged to disable security protections broadly (such as turning off Protected View entirely), as this leaves your device vulnerable to malicious files. The recommended approach is to add only specific, known-safe locations to your Trusted Sites list.

Microsoft Office Security Issues