I have several TDK DVD-R discs that have stopped playing
 

I have several TDK DVD-R 8x discs that have stopped playing any video or audio. I have tried to play the discs in several different dvd players, to no avail. The discs are not damaged in any way. the default message says that the machine does not recognize the format. My question, can the data on the discs be retrieved? Thanks

It depends on the specifics of these disks, how they were recorded, and whether or not they are damaged (e.g., not-visible damage as might come from heat/light that is excessive for the dyes on the disk).
Do you know the history of the disks? Are they pure DVD video discs, or some other format on DVD-R media?
Will they play in the original recorder? That would be my first test if possible.

In general, If a DVD disk is not "finalized" it may not play in any other type machine, although it may play in similar make/models. This is a typical issue with media that was recorded on in a DVD recorder, such as is often used to directly convert analog video to a DVD. It not likely to be an issue with DVD burned by a DVD authoring system. If this is the case it should be possible to finalize the disk in the recorder that created it.

Thank you for the prompt reply. The discs are not damaged, they have been stored in a metal briefcase. How can I tell if the discs are pure DVD video discs? Unfortunately, I no longer have the original machine they were recorded on. I have had several DVD players that have played the discs in question including my desktop computer. There was never a problem until recently all the TDK discs I described just stopped playing. Hopefully this has given you more information. I suppose my question is, is there anyway the info on these discs can be recovered and transferred to another disc?

Look at the top surface (the label side) of the discs. Press here and there with a finger. If you see bubbles, depressions, or wrinkle, the layers are coming apart. I had that problkem with some old TDK, Fuji, and SONY discs. I fixed a couple of them by leaving about 15 pounds of hardcover books on the disc for half a day (sometimes sitting on the pile for a bit, which needs a hard, flat surface under the disc). I had to copy IFO files one at a time on my PC, when the layers started coming apart again. So I repeated that process until I was able to copy all of the Video_TS IFO files. From there I re-authored to new discs. With some discs, I never did get all of it fixed.

I haven't had that problem with Verbatim AZO DVD-R. I haven't used other brands for years.

In the event the pressing method does not work are you aware of any professional company that I could the discs to for a transfer? Thanks

Sorry, no idea. Contact lordsmurf or the services staff. They might have some sources.

With H2CDimage I already succeeded and also with unstoppable copier.
Unfortunately, I have from former times only the German description as a PDF.
But, perhaps, this can translate somebody
At that time I needed, however, different DVD distiller to it then functioned.
This is why I also have even today a good 15 different DVDs / HD DVD and CD+BR.