There is some information on upgrading available in the DotNetNuke Wiki:
http://www.dotnetnuke.com/Resources/W...

You should upgrade from 4.08.00 to 4.09.05 then to 5.04.04 then to 5.06.02 making filesystem and database backups before each upgrade step and testing for and if necessary correcting any issues before proceeding to the next version step. Note the following tips (not a complete list):

1. DotNetNuke v 5.02.00 and later require ASP.Net 3.5 SP 1 and MS SQL Server 2005 or 2008 (standard or express editions) to be installed. DotNetNuke v 5.04.04 and later can also run under ASP.Net 4.0.
2. Upgrade to latest version (4.03.05) or uninstall Xml module before upgrading to DNN 5.04.04.
3. Uninstall chat module before upgrading to any DotNetNuke 5.x versions.
4. Upgrade Events module to latest version (5.01.05) after upgrade to DotNetNuke 5.04.04.
5. Upgrade Gallery module to latest version (4.03.03) after upgrade to DNN 4.09.05.
6. Check with vendors/developers of any third-party modules for upgrade compatibility information.

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Bill, WESNet Designs
Team Lead - DotNetNuke Gallery Module Project (Not Actively Being Developed)
Extensions Forge Projects . . .
Current: UserExport, ContentDeJour, ePrayer, DNN NewsTicker, By Invitation
Coming Soon: FRBO-For Rent By Owner

I have spent the best part of today upgrading 7 of our sites.  A couple were DNN 5+ but the others were DNN 4.8.4.
I found the easiest way to upgrade was to do as you stated - backup database and webfiles first.  I had a few issues with the application pool after upgrading but I do not know why.

I used the DNN 5.6.2 install, rather than the upgrade file because I have found there may be changes within the .config file between 4 & 5 that make the whole procedure rather messy to figure out should things go wrong.

I am not sure if you have rdp access to your server, but if you do not, I suggest creating an app_offline.htm file and uploading to the root directory to take the site offline while the files upload, or you can use your control panel software to unzip files however, I have found that it's better to have the config file ready and completed and putting in the url path /install/install.aspx to run the upgrade script.

The issue I had with the application pool was some duplication which required deletion of duplicate files in the GAC folder which I do not like to touch, so I ended up creating a new application pool and assigning a 4.0 application pool after the upgrde.

You are correct to install the necessary frameworks first, but you will also need to mind that you don't accidently use too many of the default settings that convert all the sites on that server to be using 4.0 or 3.5 framework. 

I am not sure but you might have to do a server restart after installing the framework - and even if it says it's not required, when changing frameworks and upgrading sites, I'd restart my server since there are plenty of things happening.  I could be wrong but I prefer to be on the safe side with us having hundreds of dnn sites - there's nothing more tragic that losing a nights sleep because of something that you weren't expecting to happen!

So, upgrade the framework, double check that a server restart is or is not required, create an application pool with the right frameworks before upgrading, use the install, not upgrade file, and you might get two errors on upgrade but I have not seen a problem with anything. 

On one build I had some issues with the dll files - dnn nav menu dll but then I saw the naming convention had changed - this was a 2008 install, so it might not affect you.  I removed the dll files from the folder and the upgrade went through seamlessly.

I have to admit the upgrades with DNN have been much smoother over the years and I feel that you should not have any issues.

For the record, I have not had any issues with the standard modules, except complex ones like catalook or any that specifically require a certain version of framework to be installed. Most developers have an upgrade path.  In fact, whether it's good to say this or not, I've got some DNN 3.1.3 sites which I've upgraded to dnn 5.6+ and all the modules have run. I'm not saying that it is like this in every case, but for most of them, not an issue.  I was pleasantly surprised and it further inspired me to upgrade more sites knowing that this was the case.

the .NET framework to my knowledge should not affect a website.   But we run sql on a separate machine with no IIS installed. 

I have not had a site break with DNN 5.6.2 and .NET 4.0 framework installed  but that is just my experience.

Good luck and I hope this gives you a couple of tips to help you through the process.

Nina Meiers

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