I had 4.5.0 up and running good.  I then tried installing the 4.5.1 update.  It would run, but I could no longer do mixed-mode authentication.  I could still log in using a superuser account, but nothing was in the logs. 

I tried a bunch of things, kept restoring my backup and trying something different.  Then, due to my own stupidity, my automated backup wrote over the backup copy I was using.  Now I'm stuck with a copy of 4.5.1 installed that won't do AD authentication...

So, I have no choice but to get this install working now, does anyone have any ideas of what might have happened?  I used the 4.5.1 upgrade install (even downloaded a fresh copy) over a known-working install of 4.5.0, using the same web.config, and there is nothing in the event viewer (in either DNN or Windows).  When I go to http://webserver/Admin/Security/WindowsSignin.aspx, it just brings be back to the home page, without logging me in.  Superuser accounts still work, so I'm able to get in and do things...

Actually, when I upgraded to 4.5.0, I didn't change the web.config and it ran okay except for some errors.  So, I took the web.config from 4.5.1 (I had already downloaded that) , updated that in put it in place with 4.5.0 and it ran fine with no errors at all.

So, I'm running the right one, there weren't all that many changes to be made.  Can you think of where to start trouble-shooting?

Ahhh... We can log in again into this website...  To continue where we left off in e-mail:

I finally got that .dll file out of the .Net framework cache.  I wasn't able to find a utility that "only" flushed the cache, so I did a repair of the .Net 2.0 installation.  That cleared that file out, and hopefully any others that were there.    However, I just checked the logs again and found this:

AssemblyVersion: 04.05.01
PortalID: -1
PortalName:
UserID: -1
UserName:
ActiveTabID: -1
ActiveTabName:
RawURL: /Schools/AlternativeHighSchool/AHSImageGallery/tabid/228/path/Fridays/currentstrip/2/Default.aspx
AbsoluteURL: /Schools/AlternativeHighSchool/AHSImageGallery/tabid/228/path/Fridays/currentstrip/2/Default.aspx
AbsoluteURLReferrer: http://www.mapsnet.org/Schools/AlternativeHighSchool/AHSImageGallery/tabid/228/path/Fridays/Default.aspx
UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.1; .NET CLR 3.0.04506.30)
DefaultDataProvider: DotNetNuke.Data.SqlDataProvider, DotNetNuke.SqlDataProvider
ExceptionGUID: 858f8809-4fa0-4b0c-91dc-9adc07d96efd
InnerException: Could not load type 'DailyComic.DailyComicController'.
FileName:
FileLineNumber: 0
FileColumnNumber: 0
Method: System.Web.Compilation.BuildManager.GetType
StackTrace:
Message: System.Web.HttpException: Could not load type 'DailyComic.DailyComicController'. at System.Web.Compilation.BuildManager.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase) at DotNetNuke.Framework.Reflection.CreateType(String TypeName, String CacheKey, Boolean UseCache, Boolean IgnoreErrors)
Source:

I did a file search, and there are no files with those names in either the DNN directory structure, and (this time) none in the .Net cache.  Why it is still trying to load the 'DailyComic.DailyComicController' is beyond me...

So, sorry to say, the problem still exists.  I'll have to try more accounts, but it seems that some accounts will work, while others don't (mostly students work, while staff don't).  It appears to be a user-level problem, in that I had a student log in and test it successfully, and I logged in shortly afterwards it would not work (from the same computer). 

It doesn't really make all that much sense...  I checked the IIS logs, and it is resolving the correct URL, and even resolving the domain name.  Other than that, there are no log entries in the DNN event viewer or the Windows Event logs.   Until I inadvertantly overwrote my backup of 4.5.0, I was able to switch back and forth quite quickly.  I had a working install of 4.5.0, then installed the 4.5.1 upgrade over it and it would stop working.  I would then restore the backup of 4.5.0, and it would start working again.  All this is was with no other changes to the server, so I can narrow it down to DNN.