Cookie per browser instance

We have a ASP.Net system, when the user logs in he gets a cookie that includes the user name.

This works fine, when there is a single user using the machine.

Where we have problems is when a user is testing the system having many browsers open and logging in with many id's.

In this开发者_运维技巧 case all browser instances will be logged in with the last user to log in.

Is there are way to be logged in with different users to different browser instances / tabs.

Yes you can do this as long as each browser is different.

It won't work if you open 4 copies of IE, but it will work if you open one copy of IE, one of Firefox, one of Chrome, one of Safari. Cookies are saved per browser, not per browser window.