# Clients encounter the 404 Not Found error after signing in to the B2CORE UI

## Problem

After signing in to the B2CORE UI and completing 2FA (if enabled), a client encounters the `404 Not Found` error and sees a blank page.

## Possible reasons

This issue may occur if the client doesn't have permissions to view the main menu due to restrictions based on **verification level** or **client type**.

## Solution

To check and update the main menu visibility settings:

{% stepper %}
{% step %}
In the Back Office, navigate to **Promotion** > **Menu**.
{% endstep %}

{% step %}
Ensure that the toggle in the **Visible** column is enabled for the **General** row. If disabled, clients will remain stuck on the **Sign In** page after entering their credentials.

<figure><img src="https://514898401-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGoRxAprhHu1goANW7FXt%2Fuploads%2Fgit-blob-22f4b1243ed326f497578067580f45db7dfc0ecd%2Fpromotion-menu.png?alt=media" alt="The main menu visibility option"><figcaption><p>The main menu visibility option</p></figcaption></figure>
{% endstep %}

{% step %}
Click the **Edit** button in the **General** row to open the details.
{% endstep %}

{% step %}
Check the **Verification level allowance** and **Client type allowance** lists. Make sure the client’s verification level and client type are included in those lists; otherwise, the main menu won't be displayed to that client.

<figure><img src="https://514898401-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGoRxAprhHu1goANW7FXt%2Fuploads%2Fgit-blob-1e2bc7be3f64ff9d11c42a49d95f2154ece27f91%2Fedit-menu.png?alt=media" alt="Verification level and client type restrictions for the main menu"><figcaption><p>Verification level and client type restrictions for the main menu</p></figcaption></figure>
{% endstep %}

{% step %}
Click **Save** to apply the changes.
{% endstep %}

{% step %}
Click the **eye** icon located in the **General** row to view the menu tree.

<figure><img src="https://514898401-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGoRxAprhHu1goANW7FXt%2Fuploads%2Fgit-blob-4465dbe1296cc851ae7f8fc2a8900265ddcf3f8a%2Fpromotion-menu-tree.png?alt=media" alt="The menu tree"><figcaption><p>The menu tree</p></figcaption></figure>
{% endstep %}

{% step %}
Verify that the **Visible** toggle is enabled for all menu items that you want to display in the main menu.
{% endstep %}

{% step %}
For each menu item, click the **Edit** button and check the **Verification level allowance** and **Client type allowance** lists. Adjust them if necessary.
{% endstep %}
{% endstepper %}

The **Visible** toggle must be enabled for the **General** row and all required menu items. In addition, the **Verification level allowance** and **Client type allowance** lists for both the **General** row and menu items must be properly configured to ensure that clients with the appropriate verification levels and client types can access the menu.