The old Virto Calendar add-in stopped working: how to switch to the Virto Calendar web part
Until 2026, Virto Calendar App was also available as a SharePoint add-in that you added from Site contents and placed on a page as an app part. Microsoft retired SharePoint add-ins: since April 2, 2026 they no longer work in any SharePoint Online tenant (Microsoft’s announcement). Where the old app part was, users now see an error or an empty box.
Virto Calendar App itself keeps working. It now runs as a SharePoint Framework (SPFx) solution with two web parts, Virto Calendar and Virto Mini Calendar. SPFx is not affected by the retirement.
To switch, install the SPFx solution once for the tenant, then replace the old app part on each page.
Step 1: Install Virto Calendar App from Microsoft AppSource
A SharePoint Administrator or Global Administrator does this once for the tenant.
- Open Virto Calendar on Microsoft AppSource and select Get it now.
- AppSource opens the Manage apps page of the SharePoint admin center. Select Add to Apps site.
- In the Enable app panel, choose to add the app to all sites. Then the web parts are available on every site and site owners do not have to add the app themselves. Select Add.
If you did not add the app to all sites, add it to each site that needs the calendar: on the site, go to Settings > Site contents > New > App, and under From your organization select Virto Calendar Overlay.
Step 2: Grant the permissions
The first time the web part opens, a Global Administrator grants the app’s permissions for the whole organization. See Authorization & Permission Request.
Step 3: Replace the old app part on each page
- Open the page that had the old calendar and select Edit.
- Delete the old app part.
- Select +, search for Virto Calendar (or Virto Mini Calendar for the compact view) and add it.
- In the web part, choose the calendar to show. See Choosing a Specific Calendar for a Site Page.
- Republish the page.
The web part does not appear in the page toolbox
The app is installed in the tenant but not on this site. Either add it to the site (Site contents > New > App > From your organization), or ask the SharePoint Administrator to enable it for all sites in the SharePoint admin center under More features > Apps.