If you have lots of downloads from years in Download manager which are unwanted & you try to clear it from Download manager you have to delete it one by one which is time consuming.
You can easily clear all the content in download manager using below steps :
Login to Service market place and go to Software Downloads –> my download basket :
my Download Basket
Select All button on the Left of Description column click on it
Click on the Delete button
Check your download basket and Download manager now(Refresh).
If you wish to delete some of the content, simply select the downloads which you want to delete and click on delete button & refresh the download manager. Sometimes you may face the download approval problem due to abundant content in download basket, hence the document is useful for the same.