ISOs are best downloaded from the VMware site at http://downloads.vmware.com/

 

ESXi 5.x ISOs (ESXi 5.0, 5.0 Update 1, 5.1, 5.1 Update 1 and 5.5 respectively):

VMware-VMvisor-Installer-5.0.0-469512.x86_64.iso (not recommended)

VMware-VMvisor-Installer-5.0.0.update01-623860.x86_64.iso (not recommended)

VMware-VMvisor-Installer-5.1.0-799733.x86_64.iso (recommended)

VMware-VMvisor-Installer-5.1.0.update01-1065491.x86_64.iso (recommended)

VMware-VMvisor-Installer-5.5.0-1331820.x86_64.iso (recommended)

 

For Cisco UCS systems, custom versions of ESXi 5.0 and 5.1 are required to support certain configurations (for example, ESXi 5.0 and 5.1 respectively):

ESXi-5.0.0-623860-custom-Cisco-2.0.1.6.iso

ESXi-5.1.0-799733-custom-Cisco-2.1.0.3.iso

 

These Cisco UCS-specific ISOs can be obtained from Cisco or VMware.

 

If you have the hypervisor on a DVD, extract your ISO from the physical media.