WhatsApp was supported on Nokia E63 till recently. Of late, users have been complaining about not being able to have proper access to the app. It seems there are some compatibility issues with the latest changes implemented by WhatsApp in its recent updates.
You may try the following methods though which may or may not work -
1. Go to Nokia.com and search for E63 apps. If you get to find the app therein, send the link to your phone and install it on your device.
2. Visit WhatsApp.com. Go to the Downloads link, select the platform as Symbian S60. Click on the link and install it on your phone.
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