Official support for vSphere 5.5 has ended, making direct downloads from the primary VMware (now Broadcom) portal more difficult to find. You can typically obtain the installer through these methods:
Avoid vSphere Client 5.5 on Windows 10. If you absolutely must manage a vSphere 5.5 environment from Windows 10, use the web client or a Windows 7/8.1 VM as a jumpbox. vmware vsphere client 5.5 download windows 10 64 bit
If compatibility mode fails, extract the MSI: Official support for vSphere 5
This indicates a Windows Installer package problem. vmware vsphere client 5.5 download windows 10 64 bit
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