> ## Documentation Index
> Fetch the complete documentation index at: https://v0.x-docs.novu.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Push

### Can I send a Desktop Push notification?

Yes, Desktop Push Notifications can be sent by using a Web Push Notification. It is supported with almost all [push channel](/channels-and-providers/push/overview) providers.

### Why am I getting the error “unexpected provider” with FCM?

The possible reasons for this error are:

* Invalid FCM credentials.
* Invalid or stale FCM token.

### Why am I getting the error “Sending message failed due to Requested entity was not found” with FCM?

* This error occurs when the FCM token is invalid or stale. You can fix this by updating the FCM device token.

### Can I store device tokens for particular FCM integration if I have multiple FCM providers active?

* Device tokens for particular FCM integration can be stored using the `integrationIdentifier` field of [update subscriber credentials api](/api-reference/subscribers/update-subscriber-credentials). `integrationIdentifier` is the unique identifier of the integration which is similar to `providerIdentifier`. It can be copied from the integration form.

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  If your question is not answered here, feel free to reach out us at [support@novu.co](mailto:support@novu.co)
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