Asp.net Webforms application when logout redirecting to a URL which does not exists

I am facing this issue from a very long time, probably when I started working in .Net 4.0. Whenever, my application is idle session and all cookie information get expired and results in logout. This logout returns to a path which does not exists.

http://localhost:2735/Account/Login?ReturnUrl=%2fadmin%2fActivities.aspx

If I closely look the url, it seems like Account/login is default path of Asp.Net MVC Application and while fail to login it redirects there.

Moreover, this is the detailed error report:

Detailed Error Information: Module IIS Web Core Notification MapRequestHandler Handler StaticFile Error Code 0x80070002 Requested URL http://localhost:2735/Account/Login?ReturnUrl=%2fadmin%2fActivities.aspx Physical Path C:\Users\Envy\Desktop\myapp\Account\Login Logon Method Anonymous Logon User Anonymous Request Tracing Directory C:\Users\Envy\Documents\IISExpress\TraceLogFiles\INSTITUTE

For login purposes, I am using simple Login control and all the stuff getting handled by it.