How to solve error 'Unable to find assembly 'EntityFramework, Version=,' ?

Programming, error messages and sample code
When you get error as below, please make sure you have enough space for your database, you can login to your control panel -->database Manager --> Mssql manager, click manager icon beside the database to view the database space usage, and edit the database space quota.

Exception: System.Runtime.Serialization.SerializationException
Message: Unable to find assembly 'EntityFramework, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089'.