Checkout Issue on Paypal: Invalid Email Address … Post author:larry Post published:Dec 20, 2005 Post category:Diary Check access rights for the key, certificate, and those directories holding these files! Not the email address issue, but the issue is that webserver can’t access the key or cert. thus it couldn’t pass it to Paypal. You Might Also Like WordPress FAQs Plugin missing Categories Feb 17, 2014 1st week report to duty Nov 10, 2006 Preliminary Solution for PMP supported format Feb 23, 2006