How to unprotect the memory card (by 11 users)

I cannot because I am unfamiliar with your camera and card.
I can suggest two more things.
1. look up[Google?] the type of card you have and try to see if you can glean any information from there - some cards have a tiny switch, other rely on a camera switch.
Does your camera have a switch with a 'Key sybol on it?
What sort of computer do you have that does not 'know' Adobe document reader?
It is universal I believe.
and is free to download.
Finally go the the customer support at Panasonic - where you may be able to download some FAQ's to search or a Q&A box.

the switch is self evident on either he card or the camera in they have such a thing.
As staed spme cards do have them other do not
the same with the camera there is a switch with a 'Key' symbol if hr has one.
If you cannot see such a thing then your model does not have it.
If you stll cannot locate a source for your problems try the customer support at Panasonic