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The following installation instructions apply to WSO2 ESB version 4.5.x onwards. But in newer versions of ESB (from ESB 4.6.0), BAM mediator will be there out of the box. If BAM mediator comes out of the box there is no need to install the BAM mediator.
1. Download the WSO2 ESB from location: http://wso2.com/products/enterprise-service-bus.
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