Problems with Thumbnailview

Hello,
I use cam2pc with my Canon EOS 300D and fomerly with an Ixus V3.
I have different problems with the thumbnail-view with pictures from the 300D. There are always exif-picture-infos on every file, but if i download the pictures to cam2pc, some pictures have a thumbnail, others not. The pictures are from the same shooting. I proofed with other the programs the existance of the exif-picture infos.
After clicking around on delete, optimize and update thumbnails they are correctly dislayed. hmm :-o??? I dont know why.
Another effect is, that the pictures taken in landscape-format with the EOS 300D are displayed with a black border at the top and the bottom. The pictures taken in portrait-format dont have these ugly borders.
I know, if i press "update thumbnail" the pictures are correctly displayd in thumbnail-view.
Can you help me?
I use cam2pc with my Canon EOS 300D and fomerly with an Ixus V3.
I have different problems with the thumbnail-view with pictures from the 300D. There are always exif-picture-infos on every file, but if i download the pictures to cam2pc, some pictures have a thumbnail, others not. The pictures are from the same shooting. I proofed with other the programs the existance of the exif-picture infos.
After clicking around on delete, optimize and update thumbnails they are correctly dislayed. hmm :-o??? I dont know why.
Another effect is, that the pictures taken in landscape-format with the EOS 300D are displayed with a black border at the top and the bottom. The pictures taken in portrait-format dont have these ugly borders.
I know, if i press "update thumbnail" the pictures are correctly displayd in thumbnail-view.
Can you help me?