# Custom Error Messages - NiceProtect Configuration

> Customize error messages shown to users when a debugger is detected or file integrity is compromised.

Canonical HTML: <https://www.niceprotect.com/help/custom_messages.htm>

## Custom Messages

- **Use anti-debug protection**


This option activates the detection of active debuggers in the system memory. If a debugger is detected, the application can either terminate immediately or display a custom warning message (configurable in the **Custom Messages** tab).

![DotFix NiceProtect Anti-debug Message](https://www.niceprotect.com/images/help/msg.png)

- **Use startup message** (Nag Screen)


Enabling this option displays a message box every time the protected application is launched. This is commonly used for trial versions to remind users to purchase a license.


Example text:

**You are currently using the DEMO version of this software.**

**Functionality is limited. To unlock full features,**

**please purchase a license at www.yoursite.com.**


You can fully customize this text in the **Custom Messages** section.

![DotFix NiceProtect Startup Message](https://www.niceprotect.com/images/help/onstart.png)


Implementing a "Nag Screen" is an effective strategy for converting trial users into paid customers by consistently reminding them of the software's commercial status.