Thanks Peter, no cache system, i never install any cache plugin on a test site 
. More, i’ve tried to clean the cache of my browser, make tests with IE, Firefox and chrome, the same…
I tried with my paypal test account connected ot not, using sandbox mode in estore or not sandbox mode, the same…
I verified the paypal adress in estore settings, it’s my merchant paypal test account
I verified all the steps to configure paypal accounts, estore and emember, it seems right. I know i missed something somqjere, but where
The most strange is that it really worked well without estore, only emember and using a paypal “buy now” button. But this was insufficiant for me because if was forced to use the same email address for buyers wp profile and paypal account
Thanks for help