Cannot import image files properly using Content Importer

I tried to import bookmap into the repository using Content Importer tool.

Topics and Maps were recognized and stored correctly in the automatically created folder.

But, image files(jpg, gif, png) were not recognized as image and stored in Others folder.

When I opened the topic in the repository with oXygen, it looks ok because image element includes format="png".

However, when I publish the bookmap to pdf or webhelp, the images for the topic is changed to the different image like [X].

I tested to import the simple topic with several images using Content Importer.

In this case, it failed with the error "invalid character in line 1, position 1" for all image.

I asked my colleague to do the same. He encountered the same error for jpg file only.

png file could be impored without any error.

Any suggestion to resolve this issue?

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