All DVD / optical media player operates
on LASER beam. When you insert media ( disc) it will try to "Sence" media by switching on the LASER beam. Beam will be reflected
from the media and give information about its type and size.
If there is some dirt ( generally dust) LASER beam will become weak
and may not provide enough information to the player so it may not rotate.What you have to do is switch of the player and unplug it. Clean Lens of the LASER pickup with a swab of fine cotton or use lens cleaner CD.
After some time. Restart the system and you will find working normally.
If there is no result, take the system to good technician.
I hope this is useful to you.
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