Estimated Time Left and Total File Size not showing up in Download

I am downloading Orcad Capture Lite software package from this official link.

I am using the Download Acceleration Plus software, even after over 350MB of the file has downloaded, I am still not able to see the Estimated Time Left or the Total size of the file:

This has never happed with anything else that I have ever downloaded.

What's wrong? Is it some kind of security measure? or some kind of error?

Answer

Most likely the HTTP/FTP server is not supplying a Content-Length response header when serving the file, so your browser/download accelerator is unable to display the file's size.