# Missing calendar invitations (Google spam policy)

Google recently implemented a new anti-spam policy that may change how your zcal invitations appear on your invitees' calendars. To ensure your meetings stay on track and your guests have a seamless experience, here is what you need to know and how you can manage it within zcal.

#### What is happening?

Google Calendar has introduced a security setting that hides invitations from "unknown senders." By default, Google now only automatically adds meetings to a recipient's calendar if the sender is someone they have previously interacted with via Gmail. This Google policy affects Google Calendar and all scheduling tools that integrate with it.

If you are sending a calendar invitation to someone for the first time, your invitation might not appear on their calendar automatically. Instead, they may see an email with a grey banner labeled **"Unknown sender: not added to calendar yet."**

#### How it affects your invitees

If your guest hasn't emailed you before, they will need to manually confirm the event by clicking **"I know the sender"** and then selecting **"Yes"** to accept the invite. This adds a bit of friction to the scheduling process that we all want to avoid.

#### Steps you can take with zcal

While this is a Google-wide policy affecting all scheduling tools, there are several ways you can use zcal’s features to minimize no-shows and ensure your meetings are confirmed:

**1. Encourage your guests to update their Google settings**\
The most permanent fix is for your invitees to adjust their own Google Calendar settings. They can go to **Settings > General > Event settings** and change the "Add invitations to my calendar" option from "Only if the sender is known" to **"Everyone."**

**2. Use zcal’s Automated Reminders**\
Since invitations might not auto-populate, it is more important than ever to keep your meeting top-of-mind. You can enable zcal’s **Email and SMS Reminders** to send a nudge to your guests before the meeting starts.

* **Pro Tip:** With a **zcal Pro** or **Business** plan, you can customize these reminder messages to include a personal note, ensuring your guest knows exactly who you are and why you're meeting.

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