WIndows Media Player11 error messages when trying to sync music

OK heres the problem and subsequent question/s. Originally, I was able to
sync music to my phone with no difficulty whatsoever. Infact, I think I
added nearly 150 songs. However, the next day when I tried adding some more
I received a few error messages, and ever since I've been trying in vain to
troubleshoot them. So if someone could please help, it would be much
appreciated.
The first thing that happens is a Windows media player device setup tab
displays. All it says is says is " name your device" and within the space it
already has filled in Vcast mobile phone. So when I click finish the first
of the error messages displays. It says "It is not possible to change sync
settings at this time. Try again later." When I go to web help it shows the
following as possible causes/solutions:
Windows Media Player Error Message Help
You've encountered error message C00D11EF while using Windows Media Player.
The following information might help you troubleshoot the issue.

Device is not responding
Windows Media Player cannot sync with the device because the device is not
responding. To resolve the problem, try one or more of the following:

Disconnect and reset the device. See your device owner's manual for specific
instructions about how to perform this procedure.

Visit the device manufacturer's Web site to find out if a firmware upgrade
is available. If so, follow the installation instructions provided with the
new firmware.

Try to sync with another device.

OK so after I close that out and actually try to sync songs the main error
displays. It says "Windows Media Player encountered a problem while
synchronizing the file to the device. For additional assistance, click Web
Help."
When I go to web help for this error-this is what it shows:

Windows Media Player Error Message Help
You've encountered error message C00D1236 while using Windows Media Player.
The following information might help you troubleshoot the issue.

Cannot sync the file
Windows Media Player encountered a problem while synchronizing the file to
the portable device. Because this error can occur for a variety of reasons,
there is no single solution.

To resolve the problem, try disconnecting and resetting the device. See your
device owner's manual for specific instructions on performing this procedure.

In some cases, this error can occur if you try to sync a hidden file to a
device. To resolve this problem, either remove the file from the sync list or
change the file's properties so that the file is not hidden.

Anyway, I cant seem to figure out how to solve this. PLease help!

That sounds like the device is partially locked up - if you reboot the
machine, does that unlock it for usage.... ?

[jack_beene]

I'm having the exact same problem. It started doing it about two weeks ago with my Chocolate (the original one), then continued with the EnV-3 I got yesterday. I've tried everything you have.