Hi

As soon as i restart my inspiron 1300 it gives me message.

The device in system modular bay can not be identified.It may not be completly inserted or may have some other problem.

After this message windows does not show CD drive. if message is not
displayed at start up, windows shows CD drive but still it does not work properly.
Can any one help me about it ?

in 99% the reason is a broken drive. you should cross check with a different drive and/or a different laptop where you can plug in the drive that doesn't work.