Plesk 9.5.4 How to enable, get https working?

hello,

1/ I have purchased and installed a ssl certificate last thursday, but when i surf to https://www.mydomain.com/testfolder/
i get a 404 Not Found page?

I expect my hello secure world! to show. What do i need to do?

2/ When configuring a website what's exactly means: Use a single directory for housing SSL and non-SSL content?
Does it mean there is no difference between the folders httpsdocs and httpdocs ?

regards