I can access it on the computer - SanDisk Sansa c250 (2 GB) MP3 Player (SDMX7-2048)

> access denied,access control configuration prevents your request being allowed

Does this happen only on ONE computer,
e.g., a computer at your school/college/university,
or one supplied by your employer?

Try a different computer.

Can you access any other site using the computer that can't access Facebook? If you can, then someone don't want you on facebook and has the site blocked or restricted.

Network Access Protection (NAP) is a Microsoft technology for controlling network access of a computer host based on the system health of the host, first introduced in Windows Server 2008.
With Network Access Protection, system administrators of an organization's computer network can define policies for system health requirements. Examples of system health requirements are whether the computer has the most recent operating system updates installed, whether the computer has the latest version of the anti-virus software signature, or whether the computer has a host-based firewall installed and enabled. Connecting or communicating computers have their health status evaluated. Computers that comply with system health requirements have full access to the network. Administrators can configure health policies that make it possible to ensure that computers not in compliance with system health requirements have restricted access to the network.

for more info. please visit the links below

http://en.wikipedia.org/wiki/Network_Access_Protection
http://msdn.microsoft.com/en-us/library/cc895519%28v=vs.85%29.aspx
http://technet.microsoft.com/en-us/network/bb545879

Are you using a "public-access" computer,
or a computer at your school, or at your place of employment?
If so, the Chief Information Officer may have _deliberately_ blocked access to FaceBook.

Tell us more about the computer you are using:
* personally-owned by you? computer owned by school/employer?
* PC? Mac?
* Windows XP? Vista? 7?
* wired Internet access? wireless?
* connected via school's network? employer's network?

to get more specific advice.

u can access it via both but when its the first time, it has to be done via wired only

When you connect the computer directly to the access point, you might not be getting IP address on your computer.
You will need to assign a static IP address on your computer in the range of default IP address of the Access point.
Click Here for More info on access point

login to your account using another computer, then make sure you logoff, or access yahoo via the computer you can access it and log off, then login using your own computer.

only one login session is permitted per user.

turen on all acces to hard drive on old xp