I'm not familiar with your recorder, but Memorex has a habit of sourcing their media from whoever is cheapest at the time, so your new Memorex DVD+RW may not be the same "under the hood" as your old Memorex DVD+RW. You could try Verbatim DVD+RW instead which is more consistent.
The DVD+R you have recorded in your recorder will need to be "finalized" in order to play in other DVD players and in your computer's DVD drive. How to do this exactly I can't tell you, but if you can't find it in the menus on your recorder, try looking in the manual.
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