UdpAnySourceMulticastClient.UnblockSource Method (IPAddress)

.NET Framework (current version)
Note: This API is now obsolete.

Unblocks a source that was previously blocked by a call to the BlockSource method so that multicast packets originating from it can be received.

Namespace:   System.Net.Sockets
Assembly:  System.Net (in System.Net.dll)

[ObsoleteAttribute("This API supports the .NET Framework infrastructure and is not intended to be used directly from your code.", 
public void UnblockSource(
	IPAddress sourceAddress


Type: System.Net.IPAddress

The address of the source to unblock.

Exception Condition

The multicast group has not yet been joined.


The UdpAnySourceMulticastClient has been disposed.


An error occurred when attempting to access the socket. See the Remarks section for more information.

The UnblockSource method unblocks multicast packets originating from a specified source address so they can be received. The specified source address must have previously been blocked by a call to the BlockSource method.

The client must have completed a join to the multicast group.

The sourceAddress parameter may be either an IPv6 or IPv4 multicast address.

If the specified source address in the sourceAddress parameter was not previously blocked by a call to the BlockSource method, a SocketException is thrown with AddressNotAvailable.

If there is a socket failure while performing the unblock source operation, a SocketException is thrown. The error received is specified as a member of the SocketError enumeration.

.NET Framework
Available since 4.5
Available since 4.0
Windows Phone Silverlight
Available since 7.1
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