Ron,
We downloaded and ran DNN 4.5.3, and unfortunately we had the same problem. DNN changes from release to release quite a bit, and since DNN devs don't test with our UltiDev Cassini each DNN release brings different compatibility level with our web server. If you communicate to DNN folks that you have interest in DNN supporting UltiDev Cassini then hopefully they start paying more attention to non-IIS use cases.
Regarding DNN 4.5.3 we've noticed that just to get through the Install Wizard we had to comment out UrlRewrite and UsersOnline modules from the <httpModules> section of the web.config, because those modules are working under assumption that only certain type of requests will be directed through those modules (which is only true for IIS in its default configuration) and therefore fail because in Cassini all modules get all requests (IIS also can be configured to route all requests to ASP.NET, which will lead to the same problem in IIS). Those modules attempt DB access on each request that reaches these modules (we wonder if that is a performance concern on its own), and since in the beginning of the Install Wizard database is not configured, most of the requests fail.
We are afraid that the bottom line is that DNN 4.5.3 is too much trouble to use with UltiDev Cassini. Consider using other versions of DNN and let DNN folks know that you are interested in DNN running in UltiDev Cassini.
Best regards,
UltiDev Team.
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