SharePoint-Progammatically create a folder using non administrator account in c#

Question

Possible Duplicate:
SharePoint -access to path is denied

I am working in SharePoint 2010,C#. I need to create a folder in my system using a sharepoint non administrator account. For example: storing the document from sharepoint document library in a folder inside D:\ drive.

 System.IO.Directory.CreateDirectory(tempPath,securityRules);

here securityRules has full control to the sharepoint logged-in user.

The problem is when the logged-in user is non administrataor then the folder is not created(access to path is denied). But administrator account works fine. Can anyone tell me how can I fix this?