Update sharp TV LE730E

Hello,
https://forums.commentcamarche.net/forum/affich-35073059-mettre-a-jour-tele-sharp-lc-43cfe6131e#p35073087
https://global.sharp/restricted/products/copier/downloads/select_fr_software.html

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If money has no smell, women have a lot of flair.

The model is not the same and I can't find anything for my model (too old???)

There is probably no update for this "old" model.
Already if we understood exactly what "I can no longer" means :-)

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"We swallow in large gulps the lie that flatters us and we drink drop by drop a truth that is bitter to us."

When I press the button to start the television, the screen stays black with the purple button lit, just like the other times when I was able to perform updates. But now it’s impossible to find anything on the Sharp website...

The least we can say is that this brand is prone to problems of this kind. The forums are filled with them.
And unfortunately, while for some the update may solve the issue, it seems that quite a few others are simply facing a component failure.
In short, unless you try to contact the manufacturer (being out of warranty doesn't mean a refusal of help), I don't see what you could do since updates are only published by the brand.

You can try a factory reset mode if such a mode exists in the manual.
Maybe there's an overload issue with the power circuit, I'm not sure, but it's worth trying this:
Unplug from the outlet and create a short circuit between the two prongs of the plug with a wire, paperclip, etc.
Of course, do not plug it back in
Wait an hour, remove the wire or paperclip, and plug it back in
(tip from Andy31200)

Thank you for your response, I will try!!!