The certificate management page of vSphere Client loads with Errors:
VMware vCenter Server 7.x
The issue occurs when a certificate is refreshed using the vSphere Client and the vSphere Client is not reloaded, or the page is not refreshed.
To resolve the issue:
1. Verify that the certificates were renewed properly and that they are all valid. Check the following KB (https://knowledge.broadcom.com/external/article/385107/vcert-scripted-vcenter-expired-certific.html)
2. Log out of the vSphere Client and log back in again to reload the page.
For more information use the following KB to check for expired Certifictaes:
https://knowledge.broadcom.com/external/article/385107/vcert-scripted-vcenter-expired-certific.html