While working on one of the Flex application I encounter below Error: Error #2173: Unable to read object in stream. The class com.util.TestClass does not

While working on one of the Flex application I encounter below Error: Error #2173: Unable to read object in stream. The class com.util.TestClass does not
There are couple of Solutions to fix this error I found below solution easy and effective. After adding Project name just change Web Module to 2.5