have a continuous running download I can't stop; blocks installation of others.
 

Attempted to download a sony updated ebook library. Was interrupted for a few minutes, then returned and started to initiate the downloading process again. With each attempt I was greeted with an error message indicating that my first download attempt was still running and further downloading was not possible until removal(stopping)of first download. It has been running for a couple of days; need to stop it.

What are you using to download? What exactly is giving the error? What exactly is the error message? What other ways have you tried to download? What have you tried to solve this?

Try 'ps aux' to find the download process or 'ps aux | grep <your-downloade-application>' for a narrow search. This will list the process number of the download, which you can kill with 'kill <process-number>'. A system restart is also a way to stop the existing download, though this depends on the downloading software. Some tools can proceed with operations after a new start, if configured to do so.

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