When you modernize a SharePoint classic team site or publishing site, the navigation menu may stop working correctly. Links disappear, the menu fails to expand, or custom navigation nodes are lost entirely. This happens because the modernization process replaces the classic master page and navigation provider with a modern SharePoint framework that does not automatically carry over custom navigation settings. This article explains why navigation breaks during classic site modernization and what site owners must check to restore and preserve their site navigation.
Key Takeaways: What to Check After Classic Site Modernization
- Site navigation settings in Site Settings > Navigation Elements: After modernization, you must re-enable structural navigation and choose which navigation type to use.
- SharePoint admin center > Active sites > Site collection > Modern navigation: The tenant-wide setting for modern navigation must be enabled for the site to use the new menu.
- PowerShell cmdlet Set-SPOHomeSite: Use this to designate a home site and enable the global navigation bar that appears in modern sites.
Why Classic Site Modernization Removes Custom Navigation
SharePoint classic sites use a master page and a server-side navigation provider that reads navigation nodes from the site map or the portal structure. When you modernize a site, SharePoint removes the classic master page and switches to a client-side rendering engine. The modern framework does not read the old navigation XML or the classic navigation settings stored in the site collection features. As a result, any custom links, headings, or flyout menus you added in the classic interface are lost.
The modernization process also changes the site template. A classic team site uses the STS#0 template, while a modern team site uses STS#3. The new template does not activate the SharePoint Server Publishing Infrastructure feature, which is required for structural navigation. Without this feature, the site reverts to the default modern navigation that only shows a flat list of pages and document libraries.
Additionally, if your site was a publishing site with managed navigation based on a term store, the modern interface does not support managed navigation at all. You must switch to a different navigation method or use the global navigation bar provided by the home site feature.
Steps to Restore Navigation After Modernization
- Check the site template and features
Go to Site Settings > Site collection features. Verify that the SharePoint Server Publishing feature is active. If it is not, click Activate. This feature enables the structural navigation settings in the navigation settings page. - Enable structural navigation
Navigate to Site Settings > Navigation Elements. Under Global Navigation, select Structural Navigation: Display the navigation items below the current site. Under Current Navigation, select Structural Navigation: Display the current site, the navigation items below the current site, and the current site’s siblings. Click OK. - Re-add custom navigation nodes
Go to Site Settings > Navigation and select the Structural Navigation tab. Click Add Heading or Add Link to recreate each custom node. Enter the URL, title, and tooltip. Set the open-in-new-window option if needed. Click OK for each node. - Enable modern navigation in the SharePoint admin center
Sign in to the SharePoint admin center with a tenant admin account. Expand Policies and select Site collections. Find your site and click its name. On the Settings tab, scroll to Modern navigation and set it to On. Click Save. - Set a home site for global navigation
Open SharePoint Online Management Shell as an admin. Connect to SharePoint with Connect-SPOService -Url https://[tenant]-admin.sharepoint.com. Run Set-SPOHomeSite -HomeSiteUrl https://[tenant].sharepoint.com/sites/yoursite. This enables the global navigation bar that displays at the top of all modern sites in the tenant. - Test navigation on multiple devices
Open the site in a private browser window. Click each navigation link to confirm it opens the correct page. Check that flyout menus appear on hover. Test on a mobile browser to ensure the menu collapses correctly.
If Navigation Still Has Issues After the Main Fix
Navigation nodes appear but links do not work
This usually happens when the URL in the navigation node points to a page that no longer exists or uses an absolute URL with the wrong domain. Open each navigation node in edit mode and verify the URL. For internal pages, use a relative URL such as /sites/yoursite/SitePages/Home.aspx. For external links, use the full https:// URL.
Modern navigation is grayed out in the admin center
The modern navigation setting is only available for site collections that use a modern template. If your site still shows the classic template in the admin center, you must complete the modernization process first. Use the SharePoint Modernization Scanner tool to identify and convert remaining classic pages. After conversion, the site template changes and the modern navigation setting becomes editable.
Global navigation bar does not show
The global navigation bar appears only on the home site and on sites that are associated with that home site. Run Get-SPOHomeSite to confirm the home site URL. If the command returns no result, run Set-SPOHomeSite again with the correct URL. Also confirm that the site is a communication site or a modern team site. Classic sites do not display the global navigation bar.
Flyout menus overlap or appear cut off
This is a CSS issue caused by the classic master page styles remaining in the site. Clear the site collection cache by going to Site Settings > Master page and clicking Reset to the default master page. Then reapply the modern theme from Site Settings > Change the look. This removes leftover classic CSS that interferes with the modern navigation layout.
Classic Navigation vs Modern Navigation: Key Differences
| Item | Classic Navigation | Modern Navigation |
|---|---|---|
| Navigation provider | Server-side ASP.NET control | Client-side SharePoint Framework (SPFx) |
| Navigation types supported | Structural, managed (term store), metadata-driven | Structural only (flat list or hub navigation) |
| Custom headings and flyouts | Supported via Navigation Settings page | Not supported in default modern menus |
| Global navigation bar | Not available | Available when a home site is set |
| Mobile responsiveness | Requires custom CSS | Built-in responsive hamburger menu |
| Performance | Slower due to server-side rendering | Faster with client-side caching |
After modernization, you can now restore your site navigation by enabling structural navigation and recreating custom nodes. Next, set a home site to enable the global navigation bar that links all modern sites in your tenant. For advanced customization, consider using the SharePoint Framework extension to build a custom navigation component that matches your classic layout exactly.