Youtube videos...are not reliant on Java, they are .flv files, requiring Flash Player. Following quote is excerpt from http://www.sothinkmedia.com/guide/video-offline.htm
, please ignore all advertising on that site...just trying to give credit to them for this useful snip of info.
"Since many video websites, such as YouTube, Google Video, Reuters.com, Yahoo! Video and MySpace choose FLV as the source file, we should know what FLV is first.
FLV (Flash Video) is a proprietary file format used to deliver video over the Internet using Adobe Flash Player (formerly known as Macromedia Flash Player) version 6, 7, 8, or 9. FLV content may also be embedded within SWF files. Notable users of the FLV format include YouTube, Google Video, Reuters.com, Yahoo! Video and MySpace."
I would try uninstalling your current version of Flash Player...then reinstalling the latest version. My guess would be that it is damaged.
Worth visiting for info on java, http://www.java.com/en/download/faq/whatis_java.xml
Edited by hamluis, 28 May 2011 - 07:59 PM.