Unless I'm missing something I have found several serious flaws in "maintenance mode" i.e. the mechanism by where DNN should lock users out whilst you are performing a software upgrade.

1. With 4.3.x when I do get the maintenance mode page to appear (i.e. all new files uploaded without having run http://mysite/Install/Install.aspx?mode=Install yet) if an incoming user tries to browse more than one page DNN starts serving up website pages again!!!

2. The DNN 4.3.x version the DotNetNuke.dll is incompatible with older 4.x releases so you can't upload it to make DNN show the maintenance page, that is without uploading all the DLL's, see this thread for more details:

http://dotnetnuke.com/Community/ForumsDotNetNuke/tabid/795/forumid/108/threadid/61306/scope/posts/Default.aspx

Needless to say both these issues, if they aren't a fault on my part, make me somewhat sceptical as to DNN's ability to be used for a production website. How exactly am I supposed to keep users from corrupting my DB whilst upgrades are being performed!!!

It also makes me wonder why DNN does not have a manually configurable maintenance mode to lock people out easily during upgrades.

Hi Cathal, thanks for taking the time to reply.

Regarding that tutorial, it says this;

• The first file to upload is the dotnetnuke.dll file from the bin folder
  
  
• This informs DotNetNuke that you are upgrading the website and it will now display an under construction page
• (You can view the under construction page in the Install folder)
  

This mechanism just plain doesn't work with V4.3.x... when you upload the dotnetnuke.dll it just breaks until all the other files are uploaded. Shame as this would be a good solution.

Using app_offline.htm, great tip and fortunately I am using ASP.NET 2.0 so it works. However it doesn't solve the fact that I have to put the website back online to run the upgrade and users can come into the site and clobber it at the same time

I already have auto-upgrades disabled and it still serves pages up when it should be displaying the under construction page.

Regarding the error, I can guarantee you all the connection strings are set correctly. It's the mixture of the v4.3.4 DotNetNuke.dll and the V4.0.2 for all the other DLL's causing the problem.