What are the differences between running a web app under the VS Dev Server and under IIS?

I have a huge, complex solution here, and if try running it for debugging under the Viusual Studio Development Server, I get an error "Could not load file or assembly 'soss_svcdotnet' Incorrect file format." When I run the app under IIS, I don't get the error.

This seems to be a 32 vs 64 -bit issue, but I'm sure开发者_StackOverflow there are more differences. So, I am prompted to ask, what are these differences?

Take a look at the following in regards to the error message you are getting.
Link

It could be that the soss assembly you are referencing is built for a 32bit processor and its now blowing up when you try to run it under 64. You may need to either recompile or download the 64bit version if its an external lib.

The VS Dev Server runs the website under your user account, with all of the permissions associated with that (and the fact that it's an interactive user on the computer), whereas IIS will typically run the site under a dedicated ASP.Net account, with limited permissions.