I'm a bit confused with this error. The web page has stopped working since Friday

Have had the photo album up and running for two weeks. What has changed since Friday is the MS two hotfixes applied.
I've done a rollback on the hotfixes. It has not changed anything - so i guess their is no related impact.

From here, i have no clue where to look and what to investigate

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Server Error in '/' Application.

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Configuration Error
Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.

Parser Error Message: It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS.

Source Error:


Line 40: </controls>
Line 41: </pages>
Line 42: <galleryServerPro configSource="config\galleryserverpro.config" />
Line 43: <!-- <trust level="Full"/> -->
Line 44: <globalization uiCulture="auto:en" culture="auto:en-US" />


Source File: C:\inetpub\wwwroot\galleryserverpro\web.config Line: 42



Show Additional Configuration Errors:


It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 62)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 69)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 76)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 82)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 84)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 104)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 117)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 156)
It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. (C:\inetpub\wwwroot\galleryserverpro\web.config line 158)

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Version Information: Microsoft .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053