Permission: Web App Calling Web Service

[Sachin]

Hi All,

I have following scenario.

1) Server Name: Server1
Web Site: WebUI (An ASP.NET Application)
Impersonation User: WebUIUser (Specified in Web.Config, under identity
section)
Authentication: Windows

All the following folders have read permission to "WebUIUser"

* C:\
* C:\Inetpub\wwwroot\
* C:\Inetpub\wwwroot\WebUI
* C:\Inetpub\wwwroot\WebUI\*
* C:\Inetpub\wwwroot\WebUI\bin
* C:\Inetpub\wwwroot\WebUI\bin\*
2) Server Name: Server2
Web Site: WebService (ASP.NET Web Service)
Impersonation User: WebServiceUser (Specified in Web.Config, under
identity section)
Authentication: Windows

All the following folders have read permission to "WebService"

* C:\
* C:\Inetpub\wwwroot\
* C:\Inetpub\wwwroot\WebService
* C:\Inetpub\wwwroot\WebService\*
* C:\Inetpub\wwwroot\WebService\bin
* C:\Inetpub\wwwroot\WebService\bin\*
WebUI calls the WebServcie. In the proxy, DefaultCredentials are set.

However it fails....error is HTTP 401: Unauthorised.

However, if I give read permissions to "WebUIUser" on same folders/files as
"WebService" it works fine.

My question is why "WebUIUser" needs read permissions on same folders/files
as "WebService"?

Thanks in advance
Sachin