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The following installation instructions apply to WSO2 ESB version 4.5.x onwards. But in newer versions of ESB (, BAM mediator is available by default 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 mediatoronwards and you do not have to install it separately.
1. Download the WSO2 ESB from location: http://wso2.com/products/enterprise-service-bus.
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