Then I suppose you are developing on .Net with WCF proxies.

There are two main reasons for a request to fail when everything seems ok.

• Timeout
• Message Quotas

Those are mechanisms from WCF to protect both the Client and the Server. e.g. the Server can be protected against big soap envelopes that when misused can drain the server, similar to a DOS attack.

Some of the LiveContent Architect Web Services need these values to be maximized. It really depends on the combination of class/method and soap payload.

Here are two functions that modify the settings for a ServiceEndpoint instance

		/// <summary>
		/// Apply timeouts to the endpoint
		/// </summary>
		/// <param name="endpoint">The endpoint</param>
		/// <param name="timeout">The timeout</param>
		private void ApplyTimeout(ServiceEndpoint endpoint, TimeSpan? timeout)
		{
			if (timeout != null)
			{
				endpoint.Binding.ReceiveTimeout = timeout.Value;
				endpoint.Binding.SendTimeout = timeout.Value;
			}
		}
		
		/// <summary>
		/// Applies quotas to endpoint
		/// </summary>
		/// <param name="endpoint">The endpoint</param>
		private void ApplyQuotas(ServiceEndpoint endpoint)
		{
			CustomBinding customBinding = (CustomBinding)endpoint.Binding;
			var textMessageEncoding = customBinding.Elements.Find<TextMessageEncodingBindingElement>();
			textMessageEncoding.ReaderQuotas.MaxStringContentLength = Int32.MaxValue;
			textMessageEncoding.ReaderQuotas.MaxNameTableCharCount = Int32.MaxValue;
			textMessageEncoding.ReaderQuotas.MaxArrayLength = Int32.MaxValue;
			textMessageEncoding.ReaderQuotas.MaxBytesPerRead = Int32.MaxValue;
			textMessageEncoding.ReaderQuotas.MaxDepth = 64;

			var transport = customBinding.Elements.Find<TransportBindingElement>();
			transport.MaxReceivedMessageSize = Int32.MaxValue;
			transport.MaxBufferPoolSize = Int32.MaxValue;
		}

For the Timeout there is a maximum value I believe. If you try a higher value, WCF will through an immediate exception.

For the quotas, every value above is the maximum allowed per property. 

The code should give an idea on how to move forward. You can set these values also through configuration in the .config file.

• WCF Binding Timeouts
• ReaderQuotas