How to Set Up Secure Guest Access in Microsoft Teams Without Breaking Compliance. Today, companies regularly share files, apps, and information with partners, vendors, and clients. Tools like Microsoft Teams make internal and external collaboration easier through guest access, letting external users collaborate with your team. But if guest access isn’t set up correctly, it can quickly turn into a security risk. The good news? You can control what guests can see and do. In this guide, we’ll walk through the best ways to secure guest access in Microsoft Teams. Before we begin, be sure to subscribe to NinjaOne’s IT video hub and our YouTube channel for more tech content like this. Prerequisites to Keep in Mind. Before you begin, make sure you have a few things ready. first, you’ll need: Microsoft 365 Business Premium, or an E3 or E5 license. You should also have the right permissions, such as a Global Administrator, Teams Administrator, or Compliance Administrator role. From a tools perspective, PowerShell 7 or newer is required, along with the Microsoft Teams, Microsoft Graph, and Microsoft Entra modules. Some features are optional but recommended, like Conditional Access and Microsoft Defender for Cloud Apps. And finally, using an RMM, such as NinjaOne, can help with registry or Group Policy auditing. Method 1: Enable Guest Access in Microsoft Entra. Configure guest access policies in Microsoft Entra ID to control how external users access SharePoint, Teams, and OneDrive. First check or enable guest access by entering this command using Microsoft Graph PowerShell. If it’s not configured, allow guest invitations with this command. Set guest user access restrictions to “Guest users have limited access to directory properties and memberships.” Method 2: Enable Guest Access in Microsoft Teams Admin Center. Enable guest access so external users can join Teams channels, meetings, and chats through the Teams Admin Center or PowerShell, depending on your organization’s configuration. Using the Teams Admin Center: Go to the Microsoft Teams Admin Center and open External Collaboration Overview Toggle from the three modes, Open mode, Controlled mode, and Custom mode. Choose Custom mode to Guest access to On, then configure permissions for file sharing, meetings, messaging, and calling. Finally, confirm these settings meet your organization’s compliance requirements. On PowerShell, use this code. Method 3: Configure Teams Guest Access Policies for Security. Limit what guest users can do (such as screen sharing, app integrations, connector usage, or creating channels) to keep your Microsoft Teams environment secure and collaborative. To limit risky guest capabilities, use this command. To enforce guest user messaging policy, use. Then, use the Teams Admin Center to restrict screen sharing, app integrations, external app access, and channel creation. You can build collaborative Microsoft 365 environments without giving up compliance. By controlling Microsoft Teams guest access, enforcing security policies, and running regular audits, you help clients collaborate securely and confidently. For more information, check out our official blog post on securing Microsoft Teams guest access linked in the description below.