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The maximum size of a single packet is approximately 500 bytes, which is normally insufficient to return all instances and attributes in a single request. Therefore, the client application must issue a series of requests to the controller, adjusting the starting instance with each request, in order to retrieve all of the instances.

The steps the client application must use to retrieve all the instances are as
follows:

1. Set initial instance to zero.
2. Send request.
3. When General Status = 06 is returned, there is more data to read. To
   determine the last instance sent in the reply, parse the data received from
   the Logix5000 controller to find the last instance ID returned.
4. Add one to the instance number determined in step 3.
5. Send the request again using the new instance value in the Request Path.
   When General Status = 00 Success, then all the symbol instances that are created
   have been returned.