1)    A lot of times while animating Text Blocks, Blend throws throws up an error like “Invalid XAML” which is really difficult to debug. Does anybody know the cause and the solution?

check if you have attached any event handler that has not been declared. also check the name of the controls are not duplicating...

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Maybe you can post it here. So that we can help you.

Maybe some namespace are not declared well, too.

There are so many reason to cause such a problem.

Regards,
Steve Wong (Hong Kong)
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