Internet Explorer 9 Security message popup - is this a virus?

Hi,  I've recently gotten a security message popup with Internet Explorer 9 (IE9).  Every time I go to a website, I get at least two popups with the following security message from IE9.  "A Website wants to open web content using this program on your computer"  Adobe Flash.  All my programs on my PC are up-to-date versions (thanks to Secunia).  My Norton Internet Security 2011 has the latest dat files.  I use 32bit Vista SP2, on a Dell Inspiron 530.  I have deep scanned for viruses with clean results.  I manually run 4 programs to get spyware off my PC, every week.  I don't get much spyware at all.  I've used Norton to check my registry.  All good.

 

If I disable Adobe Flash the problem goes away.  Microsoft Answers suggested that I create a new userid on my PC, which seems to work for now.  Copying all my info to the new userid would be a huge pain, not to mention risky...

 

I have researched the problem on the web, looked at Microsoft and Adobe web sites.  No help.  Running IE9 in compatibility mode doesn't help.  The problem seems to have been around since IE7, IE8 and now IE9.

 

The problem seemed to start a month ago, when I installed Google Desktop (which I have removed).  The problem never happens on the Google Search webpage!

 

Could this problem somehow be the result of a virus, trojan or rootkit, etc.? 

Thanks.