OK, I have an old 20Gib Maxtor hard drive that I formerly had Ubuntu on. I then put Windows on it because I got a better, bigger drive and installed Kubuntu on the new one. So, I then reformatted my drive and tried to install Slackware on it. (BTW, I now have CentOS on my new drive). Problem was, I always got the Grub error 15. So, I used the "shred -v -z -n 10 /dev/hda" command and purged the hard drive. I then tryed to install Slack again, but used GParted to set up two ext2 partitions, one linux swap, and one reiserfs. (It is the first time I have had to make the partitions, I usually just dedicate the whole drive then resize). So, that done, I enter Slackware setup. I go through, select my target partitions, my install source and my packages. I then told it to install, and it said about 15 seconds later setup was done and I needed to reboot. (I selected all packages), I rebooted, and once again, got the Grub Error 15.

Is my drive shot? Am I doing something wrong? This is the first time with any distro have I had this much problem installing it-although a couple tests I took highly recommended me to get Slack, as well as some friends who use it.

Have you tried booting the fresh install using the install-CD? If that works, perhaps either rerun GRUB once its booted, or try LILO. Maybe the bootsector on the drive has been 'Windows-ized' :P
You installed the bootloader where? to the MBR, or.....

This error is returned if the specified file name cannot be found, but everything else (like the disk/partition info) is OK.

Frequently, the error notes a missing kernel image file. Make sure that the file it is referring to exists on your boot partition.

To find out the exact name of your kernel, boot from the installation cd, mount your root and (if applicable) boot partition. Next, chroot into your Slackware system and check the available files to see what kernel images you have available. Then make sure grub is pointing to the correct one.

for more info on the error.

http://www.gentoo.org/doc/en/grub-error-guide.xml

p.s. above information directly from source hope it helps..

Can you give a little more information about how you're booting? Do you have two drives in the system and are booting selectively from one or the other? If so, how are you doing this: using the BIOS to select which drive to boot? Can you boot with a liveCD and post the contents of /boot/grub/menu.lst and /boot/grub/device.map?

Finally, shred was a waste of time. Shredding a disk is only necessary if you're the US government and have secure information on a drive that needs to be destroyed, you have kiddie porn you need to destroy before the cops get in the door, or you have FakeRaid metadata that's been borked, or something similar to these. Linux doesn't care what is or isn't on the disk when you install it. It'll just ignore anything already there, except for the partition table.

OK-I just had the same problem when reformatting and figured shreding might fix it.

I have two drives, but I like to only hook up one drive on install and configure my boot loader after to make sure I don't screw up something with the good drive. To my knowledge, Slackware did not install Grub unless specified, or does it? Should the slackware setup finish that fast? Also, do I leave my CD in the tray or take it out on reboot? I do not have any removable drives hooked up, so it can't be that.

So, you have windows on your first drive and Ubuntu on your second one? Does Windows still boot on your first drive? I'm not very qualified on grub. You may have to put the Ubuntu drive as your first drive and then put a chainloader and 2 map statements in your menu.lst to boot your Windows. Search on dual booting to see if you can find your situation vis-a-vis your disk setup.

My current HDD status is:

Good: 80Gb Segate HDD with CentOS on it

Not so great: 20 Gb Maxtor with: nothing, with two ext2 partitions, and one Linux-swap. I want to put Slack on this to try it out.

Assuming you're using grub on Centos, then I believe you need to add grub entries to chainload to the second drive, remap 1>0 and 0>1 (or just fix the fstab on slack) and boot Slack. I've never done this with Centos, so I can't give you particulars. Use the search key. There should be examples of chainloading grub from Centos.

I am not interested in configuring Grub at this time. I simply need/want to install Slack on my 12Gib hard drive. If I can get some help figuring out how to do it so my HDD works and so does Slackware, I am open to suggestions. Grub is another discussion for another day.

Post the output (using CentOS) of the command
fdisk -l

Does it show a valid partition table for the 12GB drive?
Have you tried mounting the partitions from CentOS.

My 12Gb HDD is not connected to my computer at this time. Like I have stated earlier, I keep them seperate until after installation. I just recently established the partitions using GParted however.

15 seconds sounds impossible. Before you reboot, you should get into a shell (Alt-F2?) and take a look at the disk partitions. /boot should contain the kernel...

Which Slackware version are you installing?

I was installing 10.2

Would you consider temporarily installing SimplyMEPIS 6 to help confirm or eliminate the drive as the problem?

One reason I suggest SimplyMEPIS (besides it being my favorite distro ) is that the install CD is a good live CD in its own right. You could use it to check the state of your Slack attempt & then see what it can do as an installer. Another reason for trying SimplyMEPIS is that the installer is so easy & simple to use -- wonderful if you are worried about hardware issues & don't need complex installer options to contend w/.

If SimplyMEPIS shows that the drive is good, then you can install Slack over it.