According to nwds-ak website. The information in this article applies to:

DotNetNuke - DNN
Upgrade Installation Options
DotNetNuke Upgrade Instructions -- DotNetNuke problems logging in after upgrade solution

If the DNN installation uses third-party modules that includes custom entries in the web.config file, the customer should consult with their vendor on the best way to perform an upgrade.

1. Rename the web.config file old_web.config

2. Extract DotNetNuke upgrade package

Now you need to extract all files from the DotNetNuke upgrade package into your root DNN folder or sub-folder if DNN is installed to a sub-folder. You will need to confirm the overwriting of your files. Once this process has completed, rename the release.config file to web.config and perform the following steps using the information from your old_web.config file

3. Update Connection Strings

Be sure that the proper connection strings are loaded for your setup, both in the <connectionstrings>and <appsettings> sections of your web config, examples are provided below.
<connectionStrings >
   
     < add  name ="SiteSqlServer" connectionString ="<yourconnectionhere>" providerName ="System.Data.SqlClient"  />
   connectionStrings >
   < appSettings>
     <!-- Database connection string (SQL Server 2000 or 2005 - kept for backwards compatability - legacy modules -->
     < add  key ="SiteSqlServer" value ="<yourconnectionhere>" />

4. Turn off AutoUpgrade

5. Copy Machine Key and Validation Key Values

Another very important item to copy over is your machine and validation keys from the old_web.config file. These are the keys used to encrypt and decrypt passwords and other information within your application. Failure to do this will result in your users including the admin and host user not being able to login. Below is an example of the machine key, the values you will be concerned with are the ones that note "<value to copy>".
<system.web >
     < machineKey  validationKey ="<value to copy>"  decryptionKey="<value to copy>"  decryption="3DES"  validation="SHA1"   />

6. Check and Update ObjectQualifer Line if necessarey

When Re-invent performs a free installation of DotNetNuke - DNN to a customers site we use an ObjectQualifer on line 321 in the web.config file before installation.   For example, if installing DNN v4 we change this line:

objectQualifier=""

to this:="DNN4"

7. Start Upgrade Process

After completing the above setup you are now ready to start the upgrade process.  You will want to delete your app_offline.htm file if you created one so that you can access your site again.  Now simply navigate to <yourSite>/Install/Install.aspx?mode=upgrade.  Once the page appears you should see a status screen that shows you the progress as the site is upgraded.  At the end you should see an upgrade complete message with a link to your portal.  You should not see ANY errors on this page, if you encountered an error be sure to note ALL information displayed so you can investigate the issues.

objectQualifier

This creates all SQL tables in the database with a Prefix of DNN4_.  This allows customers to differentiate between what tables are used for DotNetNuke and what tables are used for other applications you may have on your site.

You can check the ObjectQualifier by logging into your database to see if one was used.  If one was used you must change the ObjectQualifier line to match, otherwise leave it blank if no ObJectQualifer was used.

By default DotNetNuke will be set to "AutoUpgrade", this means that the first user to hit the default.aspx page on any portal within your DNN installation will trigger the upgrade process.  This is typically not a desired result as if an error occurs you might not be able to see the error log since the other individual started the upgrade.  The way around this is to update the "AutoUpgrade" appSetting, if you set this to "false" you will be required to navigate to the <yoururl>/Install/Install.aspx page to perform the upgrade.
<add  key ="AutoUpgrade"  value ="False"   />

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