Anonymous Access
Typically, all unknown users attempting to establish an HTTP connection with your Web server will log on as anonymous users. An unknown user is someone who does not have valid Windows NT accounts on your domain. While you may have them identify themselves by filling out a form, you will still want to use a real Windows account for these untrusted users to log on with.
Regardless of the type of authentication used, when a user establishes a connection, IIS will impersonate this user and log them onto the server as the impersonated account. For anonymous users, IIS will use a valid and well-known account (and randomly generated password) created during the installation of the Web server in Windows NT User Manager for Domains and in Internet Service Manager. The name of this account is IUSR_computername, where computername is the name of the machine the Web server is installed on. For Internet scenarios, this account typically is defined on the Web server machine; for intranet, it is part of a domain on which the IIS server is a member.
IIS lets anyone into Web Server with no access checks.
All anonymous users run as impersonated account (IUSR_computername) by default.
If Everyone group or IUSR_computername have NTFS file access allowed to the ASP file, it loads and runs.
This account has security restrictions that limit the type of Web content that anonymous users can access. By default, it is granted Log on Locally user rights. This account also has security restrictions determined by NTFS permissions and the rights granted to the anonymous user account; these limit the type of Web content anonymous users can access and anything else that impersonated thread attempts to do. If anonymous access has been disabled for the IIS virtual directory being accessed, or the anonymous account has not been granted permission to the file being accessed, access will be denied for the anonymous user. The anonymous user account will have access to any resources where the 'Everyone' account is enabled.
To allow anonymous access to your Web site:
Click Start, point to Programs, point to Administrative Tools, and then click Internet Services Manager. The Internet Information Services window appears.
Expand the tree in the left pane until your Web server is displayed.
Right-click the Web server and then click Properties.
Click the Internet Information Services tab.
Verify that
is selected in the Master Properties box.
Click Edit. The
Master Properties dialog box appears.
Click the Directory Security tab.
In the Anonymous access and authentication control frame, click Edit. The Authentication Methods dialog box appears (See Figure 5).
Select Anonymous access and click OK.