How can a Marantz CR603 find my music files on my computer?

Page 21 and 42 of your instructions.

I don't use my M-CR603 this way, so I can't advise any further. Sorry.  I took the easy way out and use AirPlay to play from my iTunes (from a computer or my iPhone) and remote control it all from the iPhone.

I have done the same with internet radio (and iPlayer radio) and play/control it all from the iPhone. (It can all be done via AirPlay from an iPod Touch or iPad too.)

Are you running Windows Media Player on your PC?  Alternatively, download TwonkyManager from www.twonky.com (free trial available).

You need to have a UPNP server running on your computer which will serve files to the Marantz. I use foobar2000 as my player and a plugin called foo_upnp which acts as a server. It has a wonderful option called "Playback Stream Capture" which basically means I can control the playback from within foobar (much nicer UI than the small display on the Marantz). Like iTunes and AirPlay but without the need to pay for a firmware update. If you're interested in this there's a thorough explanation here.

I use Windows Media Player. But somehow I cannot share the Music Library with my Marantz player. The Music Library does not find any other computer or device in the network.

Great, I downloaded foo upnp and it works! Thanks. The Marantz equipment now plays my music libraries. However, I cannot find the Playback Stream Capture Option. Can you tell me the secret of that?

You need to enable it in foobar preferences (File - Preferences) under Tools - UPnP - Server - Content, tick the Show Playback Stream Capture checkbox. Then on the Marantz go to Music Server - foobar2000, you should now have 3 options: Playlists, Media Library and Playback Stream Capture. Choose the last one and you should see Playback Stream Capture on the display, press "Enter/Memo" again (this might be the confusing part) and you should hear your foobar music with some lag (about 10-20 seconds for me, still unsure why this happens, but it doesn't bother me too much). Hope this helps.

Are you able to connect a Nas drive wirelessly (using Homeplugs to stream interner radio) ? If so what Nas is recommended and will you be able to see the music info on the system (track/album titles) ? Also can you forward/skip/rewind tracks like on CDs ?

All this streaming is kind of new to me and finding it all a bit confusing!

I bought a NAS RAID disk station (Synology DS411 slim) to serve my music files to the Marantz.  Both are connected to the network and I put a bunch of music files in the "music" directory of the diskstation but I get the same thing on the Marantz end: "(Empty)". 

The DiskStation has a thing called Audio Station which it says "utilizes AJAX technology to bring you an innovative and enjoyable listening experience. Organize music into playlists, browse your music library, and stream music over the Internet via a web browser become so easy and fun.  From now on, you can listen to the music stored on the DiskStation from anywhere by your iPod, Internet radio, and other UPnP/DLNA media servers."  But this seems to be more of a music player/streamer than a server.

It also installed a thing called ITunes music server on the diskstation.  Should I be using that?

I also have a MacBook on the network but I want the Marantz to get the music files off the DiskStation ideally.

BT.

You can see why some people would still prefer to use CDs instead. We're a long way from true plug-n-play aren't we.

You need to ensure the Synology has Media Server installed and running: see Chapter 17 of the manual, which you can download here

In short form, you need to go to into the Synology's management interface, then go to Main Menu > Package Center > Available > Medie Server > Install > Run After Installation

Then, provided your music is in the Synology's 'Music' folder (and both the Synology and Marantz are connected to the same network), the Marantz will be able to see and play it.

How can a Marantz CR603 find my music files on my computer?

Google Maps!!! Don't use Apple.

1. Click the Start button , click All Programs, and then click Windows Media Player.
2. If the Player is currently open and you’re in Now Playing mode, click the Switch to Library button in the upper-right corner of the Player.
3. Click Stream, and then click Turn on home media streaming. Turn on home media streaming won't be available on the Stream menu if streaming is already turned on.
4. On the Media streaming options page, click Turn on media streaming.  If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
5. Click OK.