I have an HF200 that has the same exact problem that you described. Did you ever find a remedy? I'd love to know how you cured it.
I have a problem - I have a Legria HF200 . It has worked fine, then one day I got it out and tried to power it up - the lens cover opened, the zoom went in and out and the viewing screen went all blue only - then zilch. It will not even power off unless you remove power lead/ battery. The lens cover will not close. I found the reset switch and used a paper clip to press it while operating the power on switch - that reset everything to normal and the camera worked. I did a couple of things - adjusted settings, checked SDHC card etc - powered off, removed battery and then later tried to power up - same problem - but this time reset switch had no effect. I have left it with both power on, power off and with no power lead/ battery in place for hours at a time to cool off - all with zero effect. Desperate for any other ideas before I send it for expensive repair etc..
Thanks

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