The usual suspects and causes so far are ad blockers. Sometimes resetting the browser fixes is. Chrome has it's own flash player so it just works unless there's some adblocker or malware.
After you reset the browsers and remove adblockers, if that fails, try Grif's scans at http://forums.cnet.com/7726-6122_102-5509131.html?tag=posts;msg5509131
Bob
Video on Youtube, USAToday and other sites all appear to work fine. CNET videos do a countdown, but then display a cycling circle and nothing ever plays using (Chrome v 39.0.2171.71 m). When using (IE v 8.0.7601.17514) it gives a "Stack overflow at line: 2057" or an "Out of memory at line: 833" error message depending upon whether I'm running a 32-bit or 64-bit version of IE.
This is a new Dell Optiplex 9020 office PC running Win 7 (64-bit). Have installed Java 8 Update 25, but have to maintain Java 6 Update 17, as one important office application will only work properly with that version.
Adobe Flash Player 15 is also installed along with Adobe Shockwave Player 12.1.
Any ideas?

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