"Show Preview" on file open window

[Runz]

We have 4 pc's, which are supposedly identical. Only 2 of them will show the file preview on the file=>open window.
Any ideas as to why the preview does not work on all the machines?
Thanks.

 

[PeterGuy]

Do they also fail to show the correct icon for the catia filetypes? try CATIAInstallationPath\SystemType\code\bin\cnext /regserver

Where SystemType is intel_a or Win_b64