unable to reset your pc a required partition is missing

Dear users,

I was using Ubuntu 14.04 on my laptop before. Now I want to install Win8. I have laptop's rescue CD. I get the following error when I tried to install Win8 on UEFI using the rescue CD:
"unable to reset your pc a required partition is missing"

I think I have a problem about partitions type because Ubuntu uses ext4.

How can this problem fix?

It sounds like the Rescue CD loads what it needs from a restore partition. If this partition was deleted when Linux was installed then you may have to find another way to install Windows. Try the Laptop maker's web site. There is likely a support forum to find out how to proceed.

You might see that message for several different reasons. Possibly as MilesAhead mentions, or because the process cannot find a suitable partition to place the Windows 8 image and/or one of the supporting partitions.

What is the exact condition of the target drive as far as configuration, did you remove all the Windows 8 partitions and now have a basic clean drive?

Not all recovery drives seem to be able to recover a system to a clean drive but some will. I once got the message because I had deleted the OS partition. After I recreated it and formatted, the recovery was completed, but that drive still had all the other supporting partitions.

If you check the recovery drive and look in the sources folder, do you see a file named $PBR_Diskpart.txt or something similar?

The term Rescue CD could mean several things. But if it is a CD, it is not large enough to hold the factory image. If you still have the Factory Image partition on the Hard Drive, it may be able to use that.