[TYPO3-english] lost relations to uploads folder after t3d export/import

[Markus.Kummer at t-systems.com]

Dear list members,

I have the following problem:

After I exported a typo3 site fom a 4.1.6 installation and imported it
into a 4.2.3 inst. no images which are located in the uploads folder are
shown anymore.
The images are in the right place (I copied them before) and the name of
the image is shown correctly in the properties of the CE (Pagecontent -
Media). Even the sizes and the dimensions of the images are shown
correctly (Info). In the frontend I see white space in the dimension of
the image.  
No problems with images below fileadmin.

I googled a lot but I couldn't find any solution.
Did I miss something?

Anybody can help me with that problem?
 
Best regards,

Markus