> Source: [sk184559](https://support.checkpoint.com/results/sk/sk184559)

# sk184559 - Preboot Authentication Fails with "Invalid Logon" When Credentials Contain Accent Characters

| Property | Value |
|----------|-------|
| Solution ID | sk184559 |
| Date Created | 2026-01-30 |
| Last Modified | 2026-02-09 |
| Technical Level | Advanced |
| Products | Endpoint Security |
| Versions | E89.X, E88.X |

## Symptoms

- Preboot authentication displays the error `Invalid Logon` when the user enters credentials that include accent characters.

## Cause

When the user enters a double?encoded accent character, the system interprets it as separate characters. This causes the authentication field to receive incorrect input, resulting in a failed logon attempt.

## Solution

This solution requires authentication. Please log in to view the full solution.

---

# Agent Instructions

This content is from the Check Point Support Center (https://support.checkpoint.com), the official knowledge base for Check Point cybersecurity products.

## Navigating This Knowledge Base

- **Complete index**: [llms.txt](https://support.checkpoint.com/llms.txt)
- **All SK articles**: [SecureKnowledge Sitemap](https://support.checkpoint.com/sitemaps/secureknowledge-sitemap-index.xml)
- **SK article URL pattern**: `https://support.checkpoint.com/results/sk/{skId}`
- **Markdown responses**: AI bot User-Agents automatically receive `text/markdown` content