no thumbnails or preview on remote images

Hello,
 
I can´t see any thumbnails or images even in the preview window on the remote side.
The image buffer size is high enough and I tried it on different remote directories.
 

 
Use Windows 8 X64 with the latest SFTP Version.
 
Any hints?
 
Thank you very much.
 
gieri
 
 
btw. How could I upload images here into my profile?

As it turned out the Windows registry on the customer's computer got corrupted and the problem was unrelated to SmartFTP.