This was actually answered a couple of days ago. If you do a search on "phpmyadmin login" you'll find it right away. (http://forum.wampserver.com/read.php?2,117289,117295#msg-117295)
Anyway, if you haven't assigned a password, which you apparently haven't, the default username is "root" (all lowercase) and leave password blank. You can assign a password after you get logg
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