If you're looking to try out the new DNN Cambrian package, you can upgrade previous DotNetNuke installations with the following steps. Remember, as of right now, the DNN 5.0 Cambrian package available for download is a Release Candidate and should not be used in production evironments. That said, upgrading to the new 5.0 version is just as easy as it's always been. Here's how:
The first thing you'll need to do is download the Upgrade package from the dotnetnuke.com website. As with any upgrade process, there are a few things you should do PRIOR to beginning any website upgrade.
- Backup Database
- Backup All Files
- Disable Compression Tools
Once you have done your backups and downloaded the package, you'll need to unzip the Upgrade package and upload the files on top of your existing DotNetNuke files. NOTE that the Upgrade packages do not include a web.config file so you shouldn't need to worry about changing/modifying connection strings and other settings.
Once you have uploaded the files, all you need to do to trigger the upgrade is to browse to your website URL and you'll begin to see the Upgrading DotNetNuke screen along with the status of the process. When the process is complete, you will receive a link that will take you to the website.

During the upgrade, all the required files will be installed, but there may be additional files and features that are not installed such as optional skins or modules. You can quickly install these optional files after the initial upgrade by typing the following into your browser bar:
http://www.mydomain.com/install/install.aspx?mode=installresources . This will install all available resources that were not installed during the upgrade. For example, after my initial upgrade the above command resulted in the following resource installations:

To see what resources are available, you can look in the "Install" folder in the root of your directory where you can find the resources are organized by type. This is a great way to do batch resource installation. If you only want to install one or two items and not everything, you can either remove the files that you know do not want and execute the URL. Alternatively, you can rename the files you do want changing the ".resources" to ".zip" and then uploading the files through the default method of module or skin installation within your DotNetNuke portal or by using the new "Batch Install Extensions" feature found under the Host>>Extenstions menu item.
And that's it. You've been upgraded. Most upgrades are smooth sailing, but sometimes...not so much. Learning how to troubleshoot errors during installation can help save you a lot of headaches. Here's some tips to help you out.
Troubleshooting Upgrade Errors:
Check Assemblies
You may have two assemblies conflicting with each other as a result of the upgrade. Sometimes during the upgrade process, new assemblies are installed in the file structure, but the old ones aren't removed or overwritten. When this happens, delete or change the name of the suspect file. Go back to the browser and try again.
If you receive this error when upgrading to DNN Cambrian RC:
Method 'GetRoleGroupByName' in type 'DotNetNuke.Security.Membership.DNNRoleProvider' from assembly 'DotNetNuke.Provider.DNNProvider, Version=2.0.0.23759, Culture=neutral, PublicKeyToken=null' does not have an implementation.

Check the assembly folders. Most likely, you have the following conflicting files: \bin\DotNetNuke.Provider.DNNProvider.dll - 2.0.0.23759 and \bin\Providers\DotNetNuke.Provider.DNNProvider.dll - 5.0.0.20212 . If you have both of these files, delete the file in the \bin directory and leave the file in the \bin\Providers directory.
Errors during Installation

Click the link to continue to the portal where we can view the log files to try to track down the error.
Go to Host >> Host Settings >> scroll all the way to the bottom and select the 5.00.00 log file from the drop down list and hit Go

From here you will be able to view the errors that were encountered during the upgrade process as seen here:

From the error message on the screen, you can begin to troubleshoot what your specific error is. In the particular message seen above, I have a feeling that this has to do with the ActiveDirectory provider that I have already installed in my portal. So, now that I have been given more information from the log file, I am better able to decide what to do now to resolve the issue.
Yep...in this case, it was the provider. I removed the existing ActiveDirectory package and installed the new ActiveDirectory package for DNN 5 manually. (Incidentally, if you run into errors during the ActiveDirectory installation, read this)
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