Kendash is correct. That is an error coming from IIS. I don’t use WAMP myself. I use IIS.
WAMP is “supposed to be” an easy, simple way to get Web Services with PHP up and running on Windows, which is why it is suggested. I tried WAMP a couple times throughout the years, but since IIS is built into Windows, I see no need to install WAMP, which uses Apache as it’s Web Server.
If you really want to use WAMP, you should disable/uninstall IIS. This is done via Add/Remove Programs > Windows Programs.
Here is a link to setting up IIS/PHP that I put together if you want to give that a go instead, since you already have IIS activated …