A dynamic string is always added to the url

Question

I have my project in MVC4. Whenever I run that on my local machine it added dynamic string everytime to the local host.

 

For eg: My default route is home/index , as soon as i run the project it returns  "http://localhost:58119/(S(pr54decrsv1qdyh1k34bhydf))/" If i try to remove the string and hit only http://localhost:58119/, it forcefully add that string again.

 

The value of string change itself dynamically whenever session changed.