you can check the options here - Settings > Preferences > Advanced > Downloads or (Mac) Opera > Preferences > Advanced > Downloads. or you can try to find other relevent solutions here - http://www.opera.com/browser/tutorials/intro/layout/#main-menu
I keep getting the download dialog box every time I try and listen to a song preview on Amazon when I use opera. I have installed the following plugin's for Firefox...
VLC, Quicktime Alternative, Windows Media Player and acrobat and they all seem to be working. The download dialog box has a check box to remember my choice and don't show the box again but when I try to check the box it doesn't check. Clicking open plays the file in VLC which is fine if I could get rid of the dialog box. Any suggestions would be appreciated. Thanks.

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