[Last Call] Learn how to a build a cloud-first strategyRegister Now

  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 2009
  • Last Modified:

What is the difference between DefaultAppPool and Classic .NET AppPool in IIS7?

I have a problem with Tiemout in IIS, in web.config the session timeout has set to 60 but after 20 min the session ends. This problem only occurs in IIS7 and not in IIS5.
After investigation, the reason was the application pool timeout. After 20 min without doing nothing in IIS ends and session is timeout.
If the application is defaultAppPool this occurs but if i change this to Classic .NET AppPool the timeout not occur.
Both of modes have idle timeout but only in DefaultAppPool occur.
Why is this? What is the difference between be a Classic .NET AppPool and DefaultAppPool?
And what is the difference in the pipeline, between Classic and Integrated?
1 Solution

the definitive definition is here:


essentially, in the old architecture, .NET managed code was executed through a plug-in (ISAPI) module.  Plug-in modules like that do not get loaded until after a lot of pre-processing work is done (like authentication and directory/file mapping etc) and so there are limitations to what you can do with .NET apps.  

in IIS7, .Net apps can be processed inside the main server pipeline, and so now you can do those things like authentication and url rewite etc with managed code applications.

kmetolaAuthor Commented:
Sorry, my fault, bad testing. The application pool timeout works the same way in Classic .NET app pool and Default application pool.
Anyway, the explanation about the difference is OK and I give you the points. Thank you.

Featured Post

Microsoft Certification Exam 74-409

VeeamĀ® is happy to provide the Microsoft community with a study guide prepared by MVP and MCT, Orin Thomas. This guide will take you through each of the exam objectives, helping you to prepare for and pass the examination.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now