I recently got a new computer at work with XP on it.
I wanted to turn it into a dual boot with Linux.
I used Qparted on a Knoppix disk to resize NTFS and presumably
created a new ext2 primary partition, and chose > File > Commit.

After rebooting in XP it seemed fine, it saw the new, smaller hard drive

Then I ran my Slackware install. I run fdisk
It complains thus:
"You will not be able to write the partition table."
"Device contains neither a valid DOS partition table..."
Doesn't look good.
on the p command I don't even see the 45Gb NTFS at all,
let alone the ext2 partition that Qparted supposedly made for me.

Is this a problem with fdisk? Did I miss a step with Qparted?
Has anyone done a resizing of an NTFS before?

Are you positive that Windows still boots fine?
In Windows disk management, can you see the 2 partitions (the ext2 partition should turn up as "unformatted" or any other kind of unrecognized)?
Reboot into Knoppix and check the partitions again. Is this by any chance a S-ATA disk?

Am I positive? Well, it seems to be running OK. I looked in the disk managment.
It shows a NTFS (Healthy) partition and the second (Healthy) partition, both of the sizes that I set up. It lists the ext2 as "unknown" - which I expected, since I have been told Windows cannot read this file system.

What do you think I should check with the partitions in Knoppix?
If there are any things you think I may have missed, please let me know.
I have set up dual boot systems before, and beyond making a partition, setting the filesystem type, number and whether it is Primary or Extended, I don't know of anything else to really look for.

Out of curiosity I just tried putting in a Fedora Core install disk. Interestingly Disk Druid had no problem at all seeing the partitions that Qparted made in Knoppix.

So, it is my conclusion that fdisk is flawed somehow.

Any insights?

Is this a S-ATA disk?
In Knoppix or Fedora, does the disk turn up as sda or hda?