First of all, you gave very little information about what you're trying to do and what the problem is. That said, here's my guess:
This message frequently comes up when you have your computer set to boot up from the CD/DVD Drive first. In other words, the pc will first look to see if there is a CD/DVD in the drive, and will attempt to boot from the CD if it thinks it's a bootable disc. If no cd/dvd is found, it will then normally try the next physical disc in the boot order, such as your hard drive.
It sounds to me like you do have a CD/DVD in your CD/DVD drive, and that it may not have been burned correctly as a "bootable" cd/dvd. I would remove the CD/DVD and let it boot to the hard drive.
Please give more information about what you are trying to do and what cd or dvd you are using.
Hi Frnds
EMM386: Warning:Address line A20 already enabled.................
further it will not boot the disk in my system how to solve the problem

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