One would hope that the 1.1 app could run under 2.0, but I know from
experience that this is not always the case.
You'll have to create Application Pools in IIS.  My understanding is
that these can be set up to handle the different framework versions,
though I haven't actually done this.

One ONE version can run inside an app pool at any given time.  Create
an app pool just for 1.1 apps and another just for 2.0 apps. They can't
both run at the same time.

Yeah. You have to create a separate application pool for each version of the
framework.

When running ASP.NET under IIS 6.0 ( W2K3 ), you need to place
1.1 applications and 2.0 applications in different Application Pools.

You can have as many Application Pools as your RAM allows but,
at the very least, you need to have 1.1 apps and 2.0 apps in separate
application pools.

If you need to, for critical applications, you can create additional
App Pools for them, so they are isolated and don't crash when
an application causes a shared Application Pool to crash.

Open the IIS Manager, scroll on the left to "Application Pools",
and create as many Application Pools as you need.

Then, assign your apps to the App Pools you created, making sure
that 1.1 apps and 2.0 apps are not assigned to the same App Pool.

Juan T. Llibre, asp.net MVP
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