If you have an HTC phone with WM6.1, the following link should solve your problem of not being able to watch youtube from your phone:
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http://www.htcwiki.com/page/Viewing+YouTube+on+Windows+Mobile?t=anon[/FONT]
[FONT='Calibri','sans-serif']The direct link to the installer is:[/FONT]
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http://forum.xda-developers.com/atta...5&d=1195040893[/FONT]
[FONT='Calibri','sans-serif']This worked on my Tilt, with WM6.1 downloaded in December 2008 from the HTC website.[/FONT]