I installed a new instance of 5.5.1   os is xp sp3 installed with wpi and sqlexpress 2005. Upon installing I opened the site in vs2010 which asked to congure asp.net to 4 which I allowed. I opened the site , logged in as host and tried to create a new page. I got the error that follows:

Server Error in '/dnntest1' Application.

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A potentially dangerous Request.QueryString value was detected from the client (error="...$SkinLst="<Use Default Site Sk...").

Description: Request Validation has detected a potentially dangerous client input value, and processing of the request has been aborted. This value may indicate an attempt to compromise the security of your application, such as a cross-site scripting attack. To allow pages to override application request validation settings, set the requestValidationMode attribute in the httpRuntime configuration section to requestValidationMode="2.0". Example: <httpRuntime requestValidationMode="2.0" />. After setting this value, you can then disable request validation by setting validateRequest="false" in the Page directive or in the <pages> configuration section. However, it is strongly recommended that your application explicitly check all inputs in this case. For more information, see http://go.microsoft.com/fwlink/?LinkId=153133.

Exception Details: System.Web.HttpRequestValidationException: A potentially dangerous Request.QueryString value was detected from the client (error="...$SkinLst="<Use Default Site Sk...").

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[HttpRequestValidationException (0x80004005): A potentially dangerous Request.QueryString value was detected from the client (error="...$SkinLst="<Use Default Site Sk...").] System.Web.HttpRequest.ValidateString(String value, String collectionKey, RequestValidationSource requestCollection) +8734868 System.Web.HttpRequest.ValidateNameValueCollection(NameValueCollection nvc, RequestValidationSource requestCollection) +122 System.Web.HttpRequest.get_QueryString() +56 DotNetNuke.HttpModules.UrlRewriteModule.RewriteUrl(HttpApplication app) in C:\CCNet_Builds\CE_Development\WorkingDirectory\Library\HttpModules\UrlRewrite\UrlRewriteModule.vb:66 DotNetNuke.HttpModules.UrlRewriteModule.OnBeginRequest(Object s, EventArgs e) in C:\CCNet_Builds\CE_Development\WorkingDirectory\Library\HttpModules\UrlRewrite\UrlRewriteModule.vb:359 System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +148 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75