Thanks for your attention, Patio.
I burned two CDs from different manufacturers. One was DataWrite, the other I didn't know but it was similar on both sides, shiny, etc., and I wasn't sure which side was the playing side - might have been both/either. Both CDs seemed to burn ok (when I used the correct side of the double-sided one). I checked them both while in the drive after burning, I think. They looked ok.
For a reason that I can't remember I had cause to check the double sided one again, not only wasn't it not recognized (either side) but I'd forgotten which side was the playing side
! I inserted it a number of times into the drive with it not recognized on any of those occasions. I can't remember whether I checked the other one (DataWrite) again or not: I was confident that the correct that had the correct files on it, as I definitely remember checking that after burning it.
So, I took the double-sided one to my W7 Pro laptop, and that read the CD without difficulty, confirming that the files were present and the right size. I was satisfied with that and labeled the CD so that I wouldn't be confused again
I thought nothing more of it, until the next day, when I needed to make another CD. I took a new, blank DataWrite one, and put in the drive of my XP computer. I tried a number of times, but it wasn't recognized. I took another, and at the second attempt it was recognized and I carried on and made the CD, a bootable one, which seemed to be fine. I haven't tried booting from it yet though, but if that doesn't work I may have done something wrong in the creation process. I used ImgBurn. The CD is still in the drive, but the next step will involve making another one ! I'm not going to try booting from it yet.
(I apologise if this account doesn't tie up with what I said earlier, but is no more likely to inaccurate than what I had previously. I have probably done a few more things since then as well)
So, I think you cannot help me further on this issue, and I think maybe the CD read/writer is going out, or I'm just putting the CDs in wrong most of the time
Dumb_Question
13.March.2013