Hello, Tillman!
Thank you for the feedback - nothing makes us more excited than users liking the Cassini.
If we had to guess why your application works in Cassini and WebDev Server and not in IIS, then it probably has to do with access privileges all these different servers have by default. UltiDev Cassini by default runs under very powerful "Local System" account. WebDev server of VS2005 runs under your logged in account, which is probably a computer administrator. IIS6 on Windows 2003 has default application pool configured to run under restricted "Network Service" account. All this means your application at some point may try to do something that requires access rights not granted to NETWORK SERVICE account, which crashes your app. Try to change your process identity in Win 2003 and see if that makes any difference. You can either create a new application pool for your application, or set <identity impersonaltion="true" /> in the app's web.config and then either turn on Integrated Auth, or change the Anonymous Access account to your personal user account. Keep in mind though that this will make your site less secure. If you find that this tip helped, you will probablyl have to wrap the logic that requires elevated access right into .NET Enterprise (COM+) Component component, which is not hard, and keep the rest of the application logic under Network Service account.
We hope this helps,
UltiDev Team.
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