Seona,
I'm afraid I don't have an answer for you, but I've actually experienced a similar issue. I haven't gone through the further steps that you have, as I'm not sure how to go about that. But I installed wamp64 on Win7, and went through steps 1+2 several times. I have uninstalled it twice, and have even tried installing it in a different folder. But I keep receiving the same error message
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