WMP "Play To" not working from one of my computers

My network has quite a few devices on it, so I won't bore you with the layout.
But the main topic of my issue is that I have two WD TV Live Streaming devices. My laptop is Windows 7 Ultimate 64. When I choose "Play To" on a media file to stream to either of the two devices, it says "Contacting network server" and then eventually errors out. I have gone through numerous things and all the "usual" stuff to try, but it errors out. I've reset all devices and computers, router, etc. Nothing seems to help. I also have a desktop Windows 7 Ultimate 64 and it can "Play To" absolutely fine.

Aside from the uPNP and Windows Media Player Network Sharing service, what else should I be looking for? I don't know what could be different that is preventing this from working on one system.

Thanks.

The answer is way simpler than all the answer people have been giving, and people are still having this issue, so I decided I would post the CORRECT answer, and way easier method to stop this problem. Its pathetic that Microsoft doesn't know there is an easier method than shutting down the network service, deleting the database(that is actually not corrupt), and restarting the service. Such a waste of time.

Anyway, here is the simple, no deleting, stopping, or restarting required method, that works 100% of the time.

Step 1) Open Windows Media Player, and then minimize it. (doesnt need to be minimized, just gets it out of your way.)
Step 2) Right click the file you want to stream, ie. the movie or music, select Play To and choose the device to stream/play it to.
Step 3) Enjoy the video or what ever it is.

Basically, the play to software can't initialize the playlist 95% of the time or more, because it seems it can't access the playlist if Windows Media Player isn't open (sort of makes sense I guess). So, with WMP open, it works just fine. Which is also why you can add the file to WMP and then use the Play To function from in WMP and it always works. So, leave WMP open and the Play To will work just fine. No more of that Failed to initialize crap, or hangs on connecting. Now if only Microsoft could program software properly, we wouldnt even have to open WMP!! Lol.

Bualdoot, we thank you for your effort, but unfortunately that doesn't quite do it.
At most, the remote device that is being streamed to will get a blank screen with the filename from the local computer. Even the play time and total time still read 00:00:00.
I added the file to the WMP library, let the player open, and then right clicked the file, Play to, DEVICE, and that's as far as I get. On the WMP play-to popup box, the spinning logo appears (unknown author) and eventually times out. If I hit the play button again, it just repeats the same behavior.

Must be because you are playing it from a mapped drive then. For everyone that is using a local drive, my fix will work. From a mapped drive, you are essentially streaming it twice. Once from the drive where it is located, to your computer, and then from your computer to the end device. At least, I would assume thats how it would work, if it actually was playing and not giving you an error. Since, you are instructing your computer to play it to that device, and not instructing the computer/device where the file is actually stored to play it to that device.

Although, I don't see why it would only give a blank screen with my solution, other than the fact it is not actually on your computer.

Out of curiosity, have you tried the Play To function from within WMP? On the right side, above the playlist, is a little icon that has a drop down menu for the Play To function. Does it not work from there, as well as from just right clicking the file where ever it is stored on your computer (not right clicking it in WMP)?

Well, not EVERYONE, because it doesn't work in my scenario.

Yes, I have tried it within WMP and in explorer shell. Both give same result.

Oh, and if you are getting a blank screen with file name on the device that is being streamed to, then YES, my solution did actually work. And it is infact a problem with it being a mapped drive and not being stored on your computer.

My solution is a fix for the Failed to Initialize playlist error. Not a solution to not being able to stream from a mapped drive.

Bualdoot said:

Oh, and if you are getting a blank screen with file name on the device that is being streamed to, then YES, my solution did actually work. And it is infact a problem with it being a mapped drive and not being stored on your computer.

I am not sure how I can convince any further, but this is NOT a mapped drive.
My Local C is just that, local.
I am not sure why you insist on it being a mapped drive. I have read the numerous forum threads regarding issues with mapped drives, and I am quite aware of them.

Again, thanks for the effort and insight; however my issue still lingers.

Also, a mapped drive is typically a drive not physically attached to your computer, that is essentially shared with your computer. When you set up a shared drive/folder, as a mapped drive, it appears on your computer to be a regular drive, but in reality, it is not. Is that what you are talking about with it being a mapped drive? If so, then my fix still works for EVERYONE with a local (physically attached) drive. :)