SYMPTOMS

When using web mail an error is occurring but the exact details of the message are not being displayed in the web mail client, the errror is stated to be hidden.

CAUSE

When .NET errors occur and the system is not configured to display full errors, the following error will be seen in the client.

Server Error in '/MEAdmin' or '/MEWebmail' Application.
Runtime Error
Description: An application error occurred on the server. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). It could, however, be viewed by browsers running on the local server machine.

Details: To enable the details of this specific error message to be viewable on remote machines, please create a <customErrors> tag within a "web.config" configuration file located in the root directory of the current web application. This <customErrors> tag should then have its "mode" attribute set to "Off".

<!-- Web.Config Configuration File -->

<configuration>
    <system.web>
        <customErrors mode="Off"/>
    </system.web>
</configuration>

Notes: The current error page you are seeing can be replaced by a custom error page by modifying the "defaultRedirect" attribute of the application's <customErrors> configuration tag to point to a custom error page URL.

<!-- Web.Config Configuration File -->

<configuration>
    <system.web>
        <customErrors mode="RemoteOnly" defaultRedirect="mycustompage.htm"/>
    </system.web>
</configuration>

SOLUTION

To view the correct and complete error, run the web mail client on the server. This should show the complete error. If not then it will be required edit the web.config file.  The web.config file can be found at the following location by default;

Program Files\Mail Enable\bin\NETWebAdmin\web.config

On line 35, change the following;

To change the logging, please open the above file in Notepad and then locate the line:
<customErrors mode="Off" /> and change the setting from
<customErrors mode="RemoteOnly" />  OR  <customErrors mode="ON" />

TO

<customErrors mode="Off" />

Once this is done, it is possible to copy the full error that will be displayed and send it through to MailEnable support, or use the details to diagnose and repair the error yourself. 

MORE INFORMATION

Once the error is visible, the link below may help determine the issue: http://www.mailenable.com/kb/search.asp?catalog=mailenable-KB&ST=FULL&query=.net+error