Troubleshooting "Object reference not set..."

[Medic]

After install. On page http://VAULTSERVER/VaultService/VaultService.asmx i have an error.

Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

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:


[NullReferenceException: Object reference not set to an instance of an object.]
System.Web.Hosting.ISAPIWorkerRequestInProc.GetServerVariable(String name) +1132
System.Web.Hosting.ISAPIWorkerRequest.GetServerName() +15
System.Web.HttpRequest.get_Url() +282
System.Web.Services.Protocols.ServerProtocol.CreateKey(Type protocolType, Type serverType) +90
System.Web.Services.Protocols.DocumentationServerProtocol.Initialize() +66
System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing) +99

[InvalidOperationException: Unable to handle request.]
System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing) +258
System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response) +90

[InvalidOperationException: Failed to handle request.]
System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response) +237
System.Web.Services.Protocols.WebServiceHandlerFactory.GetHandler(HttpContext context, String verb, String url, String filePath) +104
System.Web.HttpApplication.MapHttpHandler(HttpContext context, String requestType, VirtualPath path, String pathTranslated, Boolean useAppConfig) +175
System.Web.MapHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +120
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

[Beth]

Do you have Active Server Pages allowed in IIS?
How about the different versions of ASP.NET?

This KB article mentions what is going on when one can't bring up one of the web pages for Vault: http://support.sourcegear.com/viewtopic.php?t=736