What version of Windchill ?
- The thumbnail navigator?
- The Details tab?
I have a similar issue with Windchill 11.0 M020 and the new WebGL thumbnail viewer. My issue is the (3d) thumbnails don't show on the Details tab when user has their vaulting preference set to a replica site. This is only an issue with 3d thumbnails on the Details tab. The thumbnail navigator works fine. 2d thumbnails work fine in the Details tab. This issue is reproducible with FireFox, Chrome, and IE
FireFox 45.8.0 ESR
Chrome 57.0.2987.133 (64-bit)
This was not a problem with Windchill 11.0 M010 when thumbnails were viewed with the Creo View plugin.
I have a call open with PTC on this issue however no solution yet.