Windows 7 features IIS 7x, and the behavior of IIS 7 is different than previous versions.  The result of this different behavior is that if you install DNN on a Win 7 machine, you get messages like this when you try to complete the web portion of the DNN install:

Server Error in '/DotNetNuke' Application.

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Security Exception

Description: The application attempted to perform an operation not allowed by the security policy.  To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file.

Exception Details: System.Security.SecurityException: Request for the permission of type 'System.Web.AspNetHostingPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.


The solution, after much digging, was discovered by Jonathan Lawson and posted at his site. The general gist of it is:

<!--[if gte mso 9]> fficeDocumentSettings> fficeDocumentSettings> <!--[if gte mso 9]> Normal 0 unctuationKerning/> false false false oNotPromoteQF/> EN-US X-NONE X-NONE ontGrowAutofit/> ontVertAlignCellWithSp/> ontBreakConstrainedForcedTables/> ontVertAlignInTxbx/> <!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:1; mso-generic-font-family:roman; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:0 0 0 0 0 0;} @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-520092929 1073786111 9 0 415 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin-top:0in; margin-right:0in; margin-bottom:10.0pt; margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} .MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} .MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> <!--[if gte mso 10]>

Create the dotnetnuke directory in c:\webroot

Go to Control Panel -> Administrative Tools -> Internet Information Services (IIS) Manager

Expand your computer name -> Sites -> Default Web Site

Right-click the DotNetNuke directory and select ‘Convert to Application’ (I can’t remember the exact text here)

Click on Application Pools

Right-click DefaultAppPool and select Advanced Settings

In the Process Model section, set Load User Profile to ‘true’

Here's a short link to it: http://bit.ly/5AOXLs

Prior to implementing the solution above, I also found that Win 7 didn't have ASP.Net active, so I had to turn it on by doing the following:

• 1) Go to Control Panel -> Programs and Features -> Turn Windows Features On or Off
• 2) Select Internet Information Services -> World Wide Web Services -> Application Development Features
• 3) Select .Net Extensibility, ASP.Net, ISAPI Extensions, and ISAPI Filters (the latter two are automatically selected when you choose ASP.Net).
• 4) Restart my machine

Hope this helps those of you who are trying to install DNN 5 on Win 7.  FYI, I'm running Win 7 x64, I doubt that running the 32 bit version would result in changes to the above fixes, but you never know.

Thanks!