since the update customers can not login to an account or apply a coupon at the checkout, this seems to be since the newest update Magento ver. 184.108.40.206 is there any fix for this?
my website is www.alteregofitness.co.uk
It sounds as if your customer login/checkout login/cart page doesn't have a form key. Inside the form tag on each of these templates, you need to have the following:
<input name="form_key" type="hidden" value="<?php echo Mage::getSingleton('core/session')->getFormKey() ?>" />
Edit: Here is more info at the bottom of the latest patch: http://magento.com/security/patches/supee-6788-technical-details