When copying an image
from external location such as MS Word document, a PDF file or the clipboard, then its src
points to your hard disk, which is not accessible in Internet.
In order to use images in a web page, they need to be accessible using HTTP
protocol - that is, it means they must be uploaded to a web server (which can
be your own computer of course, only that the images are provided by the web
server software, and not by the operating system).
Unfortunately the automatic image upload to the server is not possible with
the browser - it would be a major security violation.
The automatic image upload cannot be implemented without using ActiveX or some
other software, installed on the client, but we do not use either technique
because of browser compatibility and that the ActiveX components are forbidden
by the corporate networks. We are specialist in ASP.NET and we cannot offer you a good ActiveX component for automatic image upload, but you can search in Google.
What we suggest is to paste the screenshot in program such as MS Paint and save
it. After that manually upload the image using the Upload functionality of the
RadEditor's Image Manager dialog and insert it into the content area after
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