# The old Virto Calendar add-in stopped working: how to switch to the Virto Calendar web part

Source: [https://docs.virtosoftware.com/docs/calendar-overlay-pro/installation-and-configuration/switching-from-the-retired-add-in/](https://docs.virtosoftware.com/docs/calendar-overlay-pro/installation-and-configuration/switching-from-the-retired-add-in/)
Product: Virto Calendar App
Updated: 2026-10-29


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](https://learn.microsoft.com/sharepoint/dev/sp-add-ins/retirement-announcement-for-add-ins)). 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.

1. Open [Virto Calendar on Microsoft AppSource](https://appsource.microsoft.com/en-us/product/office/WA200005908) and select **Get it now**.
2. AppSource opens the **Manage apps** page of the SharePoint admin center. Select **Add to Apps site**.
3. 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](https://docs.virtosoftware.com/docs/calendar-overlay-pro/installation-and-configuration/authorization-and-permission-request/index.md).

## Step 3: Replace the old app part on each page

1. Open the page that had the old calendar and select **Edit**.
2. Delete the old app part.
3. Select **+**, search for **Virto Calendar** (or **Virto Mini Calendar** for the compact view) and add it.
4. In the web part, choose the calendar to show. See [Choosing a Specific Calendar for a Site Page](https://docs.virtosoftware.com/docs/calendar-overlay-pro/installation-and-configuration/choosing-a-specific-calendar-for-a-site-page/index.md).
5. **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**.

## Related pages

- [Step 1: Install Virto Calendar App](https://docs.virtosoftware.com/docs/calendar-overlay-pro/administrators-guide-to-installation-and-configuration/step-by-step-installation-instructions/step-1-install-virto-calendar-app/index.md)
- [Adding Virto Calendar App to the Site Page](https://docs.virtosoftware.com/docs/calendar-overlay-pro/installation-and-configuration/adding-virto-calendar-app-to-the-site-page/index.md)