When trying to connect to a vCenter with PowerShell / Powercli the following error might occur.
This error happens when your vCenter is using a certificate that’s not trusted by your device.
So you have 2 solutions, the first and the best one change your vCenter certificate to a trusted one.
The second but not the preferable, ignore invalid certificates and you can do this with the command below:
Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -Confirm:$false
After this command, you will be able to connect to the vCenter without the certificate error:
Hope this was helpful.