title: ASP.NET session variables
body: <p>I have a session variable: ID.  Is there ever a possibility that two browsers on the same PC could share the same session variable and update it, therefore producing random results.  I would expect there to always be two separate sessions with two separate sets of session variables.</p>
  
  <p>I have researched this and I have come accross the following web page, which suggests that there are session locks to prevent this from happening:http://odetocode.com/blogs/scott/archive/2006/05/20/session-state-uses-a-reader-writer-lock.aspx.  I have an ASP.NET application and there are random results suggesting that this could be happening.</p>
  
  <p>I will produce some code if requested.</p>
  
  <p>UPDATE 19:51
  Tim Medora says: "two instances of the same browser type using the same session ID".  Does this mean that if a user opens one browser and then closes it (because it takes too long to open) and then opens another browser (in another window) then the same session ID could be used and the session variables in window 1 are copied for window 2?</p>
  
  <p>UPDATE 19:35 24/10/2012
  Tim Medora says: "However there is a very real possibility of two tabs in the same browser, or two instances of the same browser type using the same session ID".  Will the session information be separate in these cases.  For example, if a user opens a browser and then closes it (before the response has loaded) and then opens the same window with a different set of session variables then is there a risk that session A and session B have the same session variables.</p>