JSI Tip 1570. Windows NT DNS supports invalid characters in host names.

RFC 952 describes a name as follows:

A "name" (Net, Host, Gateway, or Domain name) is a text string up to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus sign (-), and period (.).

No blank or space characters are permitted as part of a name. No distinction is made between upper and lower case. The 1st character must be alpha and the last may NOT be a minus sign (-) or period (.).

Windows NT 4.0 DNS server does not impose these name restrictions. It will perform WINS lookup for any string, and find it (if it exists).

NOTE: Don't create an invalid name in a non-proprietary environment.

NOTE: You have no way of knowing when Microsoft may fix this, so don't use an invalid name.

TAGS: Windows 8
Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.