I get a message saying "UDF File System Error Insufficient reserve space for writing" when I insert a CD-RW/DVD-RW/DVD+RW disc into the drive.

When writing onto CD-RW/DVD-RW/DVD+RW discs, if there are damaged sectors, the data is written in substitute sectors. This message appears when there are many damaged sectors and no substitute sectors on the disc.
We recommend you copy all the data on the DVD-RW onto your hard drive and then write it onto a new disc.

If you are using a new disc and this message appears often, the drive and the disc may not be compatible. Use a brand of disc recommended by the drive manufacturer, whenever possible.

Besides, errors occur easily if the disc is scratched or dirty. Make sure your discs stored and handled carefully.