Hi Pugdog,

of course you where right.
I had included the reqiured images.
If one of them is missing the code you mention does not work.

For all of tose who try - the following helps:

<%if Image_Client%><img src="<%build_root_url%>/images/clients/<%Image_Clients('Image_Client',$ID)%>"><%else%><img src="<%build_root_url%>/images/default/ClearShim.gif"><%endif%>


where "Image_Client" is the fieldname and "<%build_root_url%>/images/clients/" my base directory for the images of clients.

The export of HTML works fine then.