Server Configuration Error Unrecognized Attribute

Issue
You receive a configuration error when opening your website:
 

Cause
This error is caused when the incorrect version of ASP.NET is used with your version of DotNetNuke.  

Resolution
Both Plesk and IIS must be configured to use the correct version of ASP.NET. See the notes at the bottom of the article if you are unsure which version of ASP.NET your site requires.

Plesk Control Panel

1. Log into your Control Panel.

• In Plesk 12

1. On the Domains tab click on the [Domain].
2. On the Websites & Domains tab click Show More then Hosting Settings
3. Under Web Scripting and Statistics section, Microsoft ASP.NET Support Version needs to be changed to the .NET version that the site has been configured to use.

• In Plesk 11

1. On the Domains tab click on the [Domain].
2. On the Websites & Domains tab click Show Advanced Operations then Website Scripting and Security
3. Under Web Scripting and Statistics section, ASP.NET Support Version needs to be changed to the .NET version that the site has been configured to use.

• In Plesk 9

1. Click Domains > [Domain] > Web Hosting Settings.
2. Under the Services section, ASP.NET Support Version needs to be changed to the .NET version that the site has been configured to use.
3. Click OK to save the changes and test your website.

Configure in IIS
If the correct ASP.NET version is already selected in the Plesk Control Panel and you are still receiving this error you must configure the site in IIS to use the correct ASP.NET. (This must be done by a support technician unless you are a dedicated server client.)

1. Click on Start > Administrative Tools > Internet Information Services (IIS) Manager.
2. Expand Application Pools. Select the [site's application pool].
3. Click on Basic Settings... under the Actions panel section.
4. Select the correct ASP.NET version from the drop down menu.
5. Click OK.

• Internet Information Services Version 7 (IIS 7)
• Internet Information Services Version 6 (IIS 6)

1. Click on Start > Administrative Tools > Internet Information Services (IIS) Manager.
2. Expand [Server], expand Web Sites.  Right click on the site and select Properties.
3. Select the ASP.NET tab and select the correct ASP.NET version from the drop down menu.
4. Click OK.

 

Notes:
DotNetNuke 6.x requires ASP.NET 4.0
DotNetNuke 5.x requires ASP.NET 2.0. Verson 5.4.4 was the first version to optionally use ASP.NET 4.0
DotNetNuke 4.x requires ASP.NET 2.0
DotNetNuke 3.x and below requires ASP.NET 1.1