Galaxy S2 can't find the songs on SD card

[asecsc4]

Dear All

I am Frustrated, mainly because I know the solution is so near and yet...

I connect my phone to the computer. I start desktop Winamp. It sees my phone, both the internal storage and the SD card.
I manually drag 10 files onto the SD card, and also a playlist that contains 4 of those cards.

All is ok.
I close desktop winamp and use File Explorer to confirm the files are on the card. They are there.

I start winamp on the phone. It does not know how to find the songs or the playlist.

What am I missing?

Please help.

Thanks
Christos