A system and method for processing messages in an enterprise resource planning (ERP) system is provided. A processing service generates a snapshot of a message queue, which contains a plurality of messages to be processed by the ERP system. Each message has an associated conversation, identified by a unique combination of an endpoint, channel, and subconversation identifier. For each conversation, the processing service determines whether messages of the conversation are to be processed in serial or in parallel, based on the subconversation identifier of the conversation. When the messages of the conversation are to be processed in serial, a task is created to process the messages serially. Alternatively, when the messages of the conversation are to be processed in parallel, a task is created for each of the messages. The messages of each task are processed serially by the task, while each task is executed in parallel with other tasks.