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FF not connecting to web- This "Network Connections" message pops up: Error 623: The system could not find the phone book entry for this connection. Any ideas?


About a month ago I could no longer connect to the internet on our PC. Every time I clicked on the Firefox icon the Netscape sign-on window would pop up. I would try to close it but it would pop up over and over again. If I tried to close it a dozen or so times eventually Firefox would open up but it would never connect. Just today I moved my Netscape file to the recycle bin. No longer does the Netscape sign-on window pop up but following Network Connection error message pops up: "Error 623: The system could not find the phone book entry for this connection".. This error window behaves the same way the Netscape sign-on window used to behave. Every time I click to close it it pops open again. After numerous clicks Firefox opens up but it never connects.

Modified by jimmythaiss1

Additional System Details

This happened

Every time Firefox opened

This started when...

About a month ago out of the blue. It never happened before.

Installed Plug-ins

  • Runs Java applets using the latest installed versions of Java. For more information: Java Embedding Plugin. Run version test: Java Information.
  • Gecko default plugin
  • iPhoto6
  • The Flip4Mac WMV Plugin allows you to view Windows Media content using QuickTime.
  • Shockwave Flash 10.0 r32
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.


  • User Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en-US; rv: Gecko/20120306 Firefox/3.6.28

More Information

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10738 solutions 96600 answers

Do you have this error message on a Mac computer or on a Windows computer?

I've only seen this error mentioned on a Windows computer.