Fixing the “circular file references are not allowed” Error in ASP.net

To resolve this problem, use one of the following methods:
Method 1: Modify the web.config file
To modify the web.config file, set the batch property of the <compilation> element in the web.config file for the
application to false.
Note: This method is recommended only for small applications. In large production applications, when you set the batch property to false, ASP.NET 2.0 compiles each page in the application into a separate assembly. The individual page assemblies are then loaded at the next available memory location. Additionally, the individual page assemblies cannot be moved. This causes memory fragmentation.
Method 2: Reorder the folders in the application
To avoid a circular reference, reorder the folders in the application. To reorder these folders, follow these steps:

1. Trace the references to the file and from the file that is indicated by the error message.
2. Identify the circular reference.
3. To avoid the circular reference, put the referenced files together in the same folder.