Blocking or Allowing MSNBot: Robots.txt and Server Configurations

Blocking or Allowing MSNBot: Robots.txt and Server Configurations

What is MSNBot

MSNBot is Microsoft’s web crawler (used by Bing) that visits sites to index pages for search results.

Using robots.txt

• Location: place at your site root as /robots.txt.
• Basic directives:
  • Allow all:
    User-agent:Disallow:

  • Block MSNBot specifically:
    User-agent: MSNBotDisallow: /

  • Allow only MSNBot but block others:
    User-agent: MSNBotDisallow:User-agent: *Disallow: /

• Specific path control: use Disallow: /private/ or Allow: /public/page.html for finer rules.
• Order/precedence: the most specific user-agent block that matches the crawler applies; multiple sections are supported.
• Crawl-delay (not universally supported): some crawlers respect Crawl-delay: 10 to slow requests, but Bing prefers crawl rate settings in webmaster tools.

HTTP response and meta tags

• X-Robots-Tag header: control indexing for non-HTML resources (images, PDFs):
  • Example header to block indexing: X-Robots-Tag: noindex
• Meta robots tag (HTML pages):
  • Use for Bing-specific rules if needed.

Server-level blocking

• By IP: configure firewall or web server to block known MSNBot IP ranges (requires maintaining IP list).
• By user-agent: web server rules can return 403 for requests with User-Agent containing MSNBot, e.g., in Apache (mod_rewrite) or nginx.
  • Warning: user-agent and IP blocks can be spoofed; less reliable than robots.txt for cooperative crawlers.

Best practices

• Prefer robots.txt for cooperative control; use server blocks only when necessary (abusive traffic).
• Use the Bing Webmaster Tools crawl settings to manage crawl rate and view crawler activity.
• Test robots.txt with online validators or Bing’s tester before deploying.
• For temporary blocking during maintenance, use 503 status with Retry-After instead of robots.txt to signal temporary unavailability.
• Keep robots.txt accessible (200 response) — if it’s unreachable, crawlers may proceed as if allowed.

Quick examples

• Block MSNBot from a folder:
  User-agent: MSNBotDisallow: /private-folder/

• Allow MSNBot but block all others:
  User-agent: MSNBotDisallow: User-agent: *Disallow: /

If you want, I can generate the exact server rules for Apache or nginx to block or allow MSNBot.