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In IIS Manager click the local computer then right-click the Web Sites or FTP Sites folder, an individual Web or FTP site, a virtual directory, or a file; and then click Properties
Note: configuration settings made at the Web or FTP Sites level are inherited by all of the Web or FTP sites on the server. You can override inheritance by configuring the individual site or site elementClick the Directory Security or File Security tab, and then do one of the following:
For Web sites, in the IP address and domain name restrictions section, click Edit
For FTP sites, continue to the next step
Click Granted access or Denied access. When you select Denied access, you deny access to all computers and domains, except to those that you specifically grant access. When you select Granted access, you grant access to all computers and domains, except to those that you specifically deny access
Click Add, and then click Single computer
Click DNS Lookup to search for computers or domains by name, rather than by IP address
Type the DNS name for the computer. IIS searches on the current domain for the computer, and if found, enters its IP address in the IP address box
It causes a performance decrease on your server while it is looking up DNS addresses
A user accessing your Web server through a proxy server appears to have the IP address of the proxy server
Some user server access problems can be corrected by entering the "*.domainname.com" syntax, rather than the "http://domainnameDomainName.com " syntax
Click OK three times
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