Please insert a disc

Dear all,
I have a windows 7 64-bit. my problem is that when I insert a CD or DVD in my DVD drive (slimetype DVD A DS8A3S) and double click or right click and open, the disk gets ejected and and I get the message that says please insert disc. That happens with all kind of disk. I searched the net and tried everything even upper and lower limits to no avail. I tried everything even I have done a fresh installation of windows 7 and that did not work. The driver seems to work fine and I can see it in device manager and it does not have a yellow exclamation mark. I even tried to delete it and let windows re-detect and re install
I took 2 months of search before writing my problem here and hope someone can help

I can only think that it is a hardware problem, did it work earlier without problems?

Thank you all for the response. I also thought it is hardware problem and yes it used to be working fine. I will also try to eliminate problems

OK I have removed my drive and replaced it by my external DVD (which I removed from the box) and it worked fine. Then I put my drive in the box and it was detected and I saw the icon but once I put the CD it gets disconnected so it seems that the drive was defective. Thanks

I'm happy to hear that you got it solved :)