Install wampserver3_x64_addon_mysql5.6.51 (no replies)

When attempting to install wampserver3_x64_addon_mysql5.6.51 on 3.2.6 I don't get the selection of the root folder but I see the error

The installation folder chosen is not that of Wampserver version 3. Select the installation folder of Wampserver 3


There is no option to select the Wampserver 3 folder.

How do I install 5.6.51?