Knowledge Article Images are not Displayed on Portals

Hi All, 

I have a CRM instance with a Portals v8 add on. I have created a Knowledge Article with text and images which was perfectly displayed on Portals. In terms of the images they were stored in Web Files in the Notes tab.

Export / Import Issue  

However, when I tried to export those Web Files and the Knowledge Article and upload them to a new instance, the image files were gone. Going to Web Files --> Notes I realized that the images wasn't there so I had to upload them manually one by one. 

But even after uploading them I still can't see any images on the Knowledge Article.  

Error Message

Navigating to ISH instead of an image a see the following picture:   

And when I double click the above and try to provide the Partial URL of the Web File, I am getting the error below:

Can you anyone please advice?

Thanks in advance.