---
title: "Before shielding an app"
slug: "oapps-tg-before-shielding-an-app"
updated: 2026-10-20T11:52:52Z
published: 2026-10-20T11:52:52Z
canonical: "docs.onespan.com/oapps-tg-before-shielding-an-app"
---

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

# Before shielding an app

The steps outlined below provide useful information when your app cannot be shielded.

## The app cannot be shielded

[Identifying issues—The app cannot be shielded](/oapps/docs/oapps-tg-before-shielding-an-app#Tab_TS_AppCannotBeShielded) contains the troubleshooting steps to identify the most common issues that can cause the [OneSpan Mobile Portal](https://mobile.onespan.com/) to display an error message when trying to shield your app.

> Go through the questions in the order they are listed until you have identified the issue.

| Identifying issues—The app cannot be shielded |
| --- |
| Step | Question | How to test | What to do |
| 1 | Is your contract still active? | Download the contract certificate and check the expiration date. | If the contract has expired, contact OneSpan Support. See also: - [Contact OneSpan Support](/oapps/docs/oapps-tg-contact-onespan-support) |
| 2 | Is your configuration archived? | On the [OneSpan Mobile Portal](https://mobile.onespan.com/), check if the Archived label is displayed next to your configuration. | Copy the configuration to the latest (or at least a newer) App Shielding version. |
| 3 | Is App Shielding up to date? | Check the available App Shielding versions on the [OneSpan Mobile Portal](https://mobile.onespan.com/). | Try again with a new App Shielding version. |
| 4 | Does the error message contain useful information? | Read the last lines of the output of the App Shielding attempt. See the output example below. | Try again, using the information from the error message. If the error message does not help, gather all relevant data and contact OneSpan support. See also: - [Contact OneSpan Support](/oapps/docs/oapps-tg-contact-onespan-support) |

> ERROR: Cannot shield the application
> 
> ERROR: Your application class com.onespan.exampleapp is annotated with @no.Vasco.shield.ui.ScreenMirroringLayoutName("view_blocking_screen_mirroring"), but your configuration config.xml has not enabled blockScreenMirroring. Either remove the annotation from the application class, or enable both checkScreenMirroring and blockScreenMirroring in the configuration. See also section 'ScreenMirroring Customised Layout' in the reference documentation.