Overview

The following error is shown when accessing the GFI MailEssentials Web Configuration UI:

Server Error in '/MailEssentials' Application.
Security Exception
Description: The application attempted to perform an operation not allowed by the security policy. To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file.
Exception Details: System.Security.SecurityException: Request for the permission of type System.Security.Permissions.FileIOPermission, mscorlib, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 failed.

 

Environment

• GFI MailEssentials
• All supported environments

 

Root Cause

This problem is caused by incompatible security settings in regard to the .NET Framework.

 

Resolution

This error can be caused by security settings which stand in conflict with the requirements of the GFI MailEssentials Web Configuration UI.

To fix this manually:

1. Go to the Windows Directory\Microsoft.NET\Framework\v1.1xxxx\CONFIG directory.
2. Open the machine.config file with a text editor (e.g. Notepad).
3. Search for a section which says location allowOverride="false".
4. Change to location allowOverride="true".
5. Restart the IISAdmin Service and its dependencies.

Notes:

• The above is the change made by the GFI MailEssentials setup when it warns about this issue during installation and asks whether it should fix the issue automatically. 
• IIS stands for Internet Information Services.