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I continually get this error message "Exc in ev handl: Error: Bad NPObject as private data!"


When I try to go to or close almost every web site. The message appears at least twice. This has happened since I upgrade to 6.0.1 (which I did as my previous version was crashing every 30 seconds or so!) While I can still do what I need to this is most time consuming and annoying. Anyone have an idea?

Chosen solution

Additional System Details

Sites Affected


Installed Plug-ins

  • Garmin Communicator Plug-In
  • np-mswmp
  • Coupons, Inc. Coupon Printer DLL
  • Coupons, Inc. Coupon Printer Plugin
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.0
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • npmnqmp 989898989877
  • BrowserPlus -- Improve your browser! -- http://browserplus.yahoo.com/
  • Shockwave Flash 10.3 r183
  • iTunes Detector Plug-in
  • Next Generation Java Plug-in 1.6.0_26 for Mozilla browsers
  • McAfee MSC FF plugin DLL
  • SiteAdvisor
  • 4.0.60531.0
  • Google Update


  • User Agent: Mozilla/5.0 (Windows NT 6.0; rv:6.0.1) Gecko/20100101 Firefox/6.0.1

More Information

finitarry 157 solutions 2175 answers

Download Firefox 6.0.1 (the entire version), then see if uninstalling Firefox, removing the Firefox program directory, and then installing the new version just downloaded fixes it. If the upgrade was done by an update, something might have gone wrong with it.

Question owner

how do I remove the pgm directory and will this mean all my bookmarks etc. will be gone? OK- just went for it, and it seems to have resolved the issue (and my profile is intact). Thanks!

Modified by quillpm

Question owner

Guess I spoke too soon. The error message is back with a vengeance. Any other ideas out there. This is driving me nuts (and away from Mozilla).

finitarry 157 solutions 2175 answers

Chosen Solution

It might be McAfee Site Advisor. https://community.mcafee.com/message/203466

KevanWebb 0 solutions 1 answers

Why you should I have to disable McCafee Site Advisor I pay for this as part of my package and I never had this problem all the time I was using Flock. For me Firefox is a nightmare as it crashes at least once a day and have problems with opening some Adobe documents. I am waiting for an updates that resolves all these issues.

  • Top 25 Contributor
  • Moderator
622 solutions 8008 answers

Hi KevanWebb,

If you have a problem with crashes and McAfee Site advisor I suggest you start your own thread about your own problems. You may find an answer.

Please ask your own question by following the links and prompts from