Can't create or write to a file w/ASP.NET: UnauthorizedAccessException

I have a C# ASP.NET 2.0 application that needs to write some simple logging records to an XML file in the bin directory under the www root.  If I attempt to create or write to the file, I get an UnauthorizedAccessException.  (Access to the path 'D:\webadmin\www\bin\test.xml' is denied).  My server administrator says the ASP.NET user has write access to the bin directory, and I'm not sure what else the problem could be.

My testing code...  this code is compiled code-behind in the bin directory (same directory I'm trying to write to) and the ASPX page is up one directory (under the root).

filepath = @"D:\webadmin\www\bin\test.xml"
if (!File.Exists(filepath)) {
      File.Create(filepath); //Error is thrown here.
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_TAD_Connect With a Mentor Commented:
Here is the standard Microsoft solution to that error:

ASP.NET is not authorized to access the requested resource. Consider granting access rights to the resource to the ASP.NET request identity. ASP.NET has a base process identity (typically {MACHINE}\ASPNET on IIS 5 or Network Service on IIS 6) that is used if the application is not impersonating. If the application is impersonating via <identity impersonate="true"/>, the identity will be the anonymous user (typically IUSR_MACHINENAME) or the authenticated request user.

To grant ASP.NET write access to a file, right-click the file in Explorer, choose "Properties" and select the Security tab. Click "Add" to add the appropriate user or group. Highlight the ASP.NET account, and check the boxes for the desired access.


If you are certain that all of these steps have been followed, try to uncheck and recheck the security access values and be sure to go into the advanced button and check the box that allows those security settings to propigate to all sub-folders and files.
Kate12Connect With a Mentor Commented:
You can easily add ACL to your file prior to creating it:

You can even use Thread.CurrentPrincipal.Identity.Name to add your current thread Principal to either the parent folder or the File Prior creation. You can also use:

FileSecurity fileSecurity = new FileSecurity(fileName, AccessControlSections.All);
File.Create(fileName, 4089, FileOptions.None, fileSecurity);

O look at FolderSecurity to give access to the entire folder

justdriveonAuthor Commented:
Even though the I had read and used the error description for this error as reiterated by _TAD_, his comment prompted me to go back to my server guy and tell him to look again.  Turns out he was checking permissions on the wrong website.  Isn't it nice when the problem is someone else's rather than your own?

I am also giving Kate12 points because when googling this problem I could not find anything about these FileSecurity/FolderSecurity classes, only Active Directory Server as in this arcticle:  So even though I didn't use it, I probably would have been able to solve the problem this way.
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