Recovery Technology
Hello Zipperlein,
You should try the following.
Put the suspiciontely damaged Disc into your freezer for an hour.
After this, take it and try to read by ordinary mode immediately. The cold condition is very important!
In most cases, the low temperature redesigns the magnetic structure, at least sufficient for an other try.
This last try should be dedicate to having a copy.
I did this often in the past, with success in apparent hopeless cases as well.
It goes without words, only in cases the disc is unreadable because of the long time run away, it works.
good luck!
Robby