cannot access vmware vsphere web client 6.5

Third, when that certificate expires, vSphere does the right thing and stops trusting the communications with the service, because it no longer has a valid certificate. Second, there is not an alarm on STS certificate expiration like there is for other certificates, warning of the expiration. First, vSphere upgrades do not refresh the STS certificate, so a two-year certificate may have been carried forward during an upgrade and is likely nearing expiration now. Normally this would not be a big problem, but three other issues have conspired to complicate this. Because of industry-wide changes to certificate expiration standards, some certificates issued by vSphere 6.5 Update 2 and newer versions of 6.5 only had a lifespan of two years, rather than the usual ten-year lifespan for that particular certificate. The VMCA is a part of vCenter Server that automates issuing certificates to these services. To enable TLS encryption you need a certificate, and that certificate is usually issued from the VMware Certificate Authority (VMCA). VSphere protects all communications between services with encryption.

To quote the vSphere documentation, the Security Token Service “is a service inside vCenter Server that issues, validates, and renews security tokens.” Any time a user logs into vCenter Server they will be issued one of these tokens as part of the Single Sign-on process, which is then used for authentication whenever a request is made.

HTTP Status 400 – Bad Request Message BadRequest, Signing certificate is not valid

Cannot access vmware vsphere web client 6.5