Download the trusted CA certificates from the vCenter landing page.
The "vSphere Web Client" (Flash-based, typically on port 9443 ) has been deprecated and removed in modern vSphere versions (7.0 and later). It has been replaced by the vSphere Client (HTML-5 based) on port 443 . vsphere web client download
The vSphere Web Client serves as the primary graphical user interface for managing VMware vSphere environments. It allows administrators to manage ESXi hosts, virtual machines, and vCenter Server instances from any modern web browser, removing the dependency on a Windows-based thick client. Download the trusted CA certificates from the vCenter
The Flash-based vSphere Web Client is removed. vsphere web client download