How do I remove pending/in-progress downloads A few days ago, I tried to save an attachment from official Gmail app and it could not finish download due to some connection errors. 

Now, I'm seeing the notification every time without any progress. It just stays in the notification area and sliding the notification does not remove the download. 

This file download was started from Gmail app and I see the same type of notification in other downloads from different apps so I'm guessing there is a central download progress going on. 
I tried turning the phone off, removing the battery and SIM.


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How can I list and remove these downloads ?
Have you tried a file explorer like ES File Explorer or My Files, which comes with later versions of Android? If go to the Download folder is the half file present? A completely downloaded file will present a long list of options if you long press the file, allowing you to cut/copy/rename/delete. Possibly it will also appear on a halfway complete download to allow you to delete. Then revisit the gmail message to restart the download if you want.Remember that the target folder might have been specified other than the Download folder.Good Luck.