windows 2012 r2 - IE - all ssl certificates invalid

Hi all,

we used the vmware converter to migrate a windows 2012 R2 Server from a local VM Ware Workstation into an ESXi 5.5 Server. The machine runs fine, but now the Internet Explorer (IE) does not trust any server certificates.

Trying to open www.google.de ends with the message "Es besteht ein Problem mit dem Sicherheitszertifikat"

Meaning: There is an error with the security certificate.

Is there a way to reactivate the certificates somehow?

Thanks in advance

Andreas