I got error like "Access to the path "C:\Temp\6ac6b599-7ea3-4dc0-8133-75804843c300.tmp" is denied"

SUMMARY

ASP.NET is not authorized so save files in temp folder (defined by tempPath parameter). 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.

SOLUTION

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

REFERENCES

NTFS File permissions:
http://technet2.microsoft.com/WindowsServer/en/library/f4aadfb4-1af4-4e27-9ff0-3a650cd476dd1033.mspx?mfr=true

ASP.NET Impersonation:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vsent7/html/vxconimpersonation.asp