I'll go along with the suggestion to try a fresh installation of Flash but there could be a problem if you simply try to install it from Tony's link. That's because Flash has a nasty habit of not installing properly if it thinks that you've got a fully-functioning version already on your computer (even when you haven't). So I'd advise uninstalling the existing version first:
Go to Start > Control Panel > Programs and Features.
Click on 'Adobe Flash Player' and then on 'Uninstall'.
After you've uninstalled Flash, RESTART YOUR COMPUTER.
(That's in capitals because it's IMPORTANT!).
Then go to Tony's link and reinstall Flash.
uninstalled and then installed Adobe flash player as instructed makes no difference, in fact it doesn't show black video just the sound.... so got a completely blank screen.
Try this Emmie go to a web page that has a you tube video posted on it.(the Bank for instance) Then right click, then click on settings. This will bring up a panel in flash player which will have Hardware Accelerator CHECKED............ UNCHECK IT and see how you go after a restart.
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