Sometimes when folks are developing on Windows XP with ASP.NET they think they can't change the security settings (ACLs) for files. This comes up when developing with dasBlog when you have you change file permissions, but also when trying to do anything tricky, like moving your ASP.NET bin folder.

Stephen Venter has a nice write-up on Enabling Windows XP File Permissions explaining the checkboxes and dancing that you have to do to enable the Security Tab in a File's Property Dialog on Windows XP Pro or Home. All this, of course, assumes you're running NTFS as your file system.