Microsoft say this about Winsock error 10013 - WSAEACCES:

An attempt was made to access a socket in a way forbidden by its access permissions. An example is using a broadcast address for sendto without broadcast permission being set using setsockopt(SO_BROADCAST). Another possible reason for the WSAEACCES error is that when the bind function is called (on Windows NT 4 SP4 or later), another application, service, or kernel mode driver is bound to the same address with exclusive access. Such exclusive access is a new feature of Windows NT 4 SP4 and later, and is implemented by using the SO_EXCLUSIVEADDRUSE option."

Full details of Winsock TCP error 10013 - WSAEACCES:

Berkeley description: An attempt was made to access a file in a way forbidden by its file access permissions.

Microsoft C description: Permission denied. The file's permission setting does not allow the specified access. This error signifies that an attempt was made to access a file (or, in some cases, a directory) in a way that is incompatible with the file's attributes. For example, the error can occur when an attempt is made to read from a file that is not open, to open an existing read-only file for writing, or to open a directory instead of a file. Under MS-DOS versions 3.0 and later, EACCES may also indicate a locking or sharing violation. The error can also occur in an attempt to rename a file or directory or to remove an existing directory.

WinSock description: Same as Berkeley.

Detailed description:

The requested address is a broadcast address, but the appropriate

flag was not set (i.e. you didn't call setsockopt(SO_BROADCAST)).