I could not open my 2007 Baxter S with my key electronically nor manually ?
Test the battery in the key with a multimeter. If it is OK, you may need to re-sync the key with the car, the procedure is in the owners manual. I don't understand your point about not opening the car manually, unless you are mistakenly using the key for another car instead of yours. By the way, it's a Porsche 'Boxster', not 'Baxter'. (Baxter is a pharmaceutical company.) The name is derived from the boxer engine and roadster body style.
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