I have undergone the same problem.
it's because of the skype,so i reintall the apache service.
it ran well. but after reboot,
I meet the same situation.
then i opened the ApacheMoniotor,
Find the i runs the apache but not the wampapache.
so i disable the apache in services.
and the wampapache worked again.
sorry for my poor english,I comes from Taiwan. : )
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