I had windows 7 and Ubuntu initially on my laptop and today i wanted to give Slackware a try and i installed it. When prompt to install lilo, i ticked no which left me with the grub already installed with my Ubuntu. Now the thing is i can boot into my Ubuntu and Win 7 but i cannot boot into my slackware, i use update-grub to find Slackware but it did not return anything and i even tried adding a custom entry though i am not sure if the entry is correct or not. After googling for a while i saw some forums that suggested that in the custom entry, i used the vmlinuz-huge instead of the generic and i also found out from some other places - correct me if i am wrong but in the Slackware's /boot folder there must exist a initrd file in order for grub to update properly. I have tried mounting my Slackware onto my ubuntu /mnt/ but now i am completely stuck. i have no idea how to make my grub see my Slackware. Help appreciated.

just to clarify, is there no initrd or something of a similar name in the boot folder?

Nope. None. I think the initrd was supposed to be made after i install lilo but i cancel when it prompted me because i am afraid of it ruining my other boots. Is there any way to mount the slackware onto my ubuntu and make a initrd for it and then add a custom entry onto my grub 2. If so how. Anyway thanks.

yes, never fear as linux has a lovely command known as chroot, it's an abreviation of "change root" and it allows you to have a CL interface with your other OS, you generally mount the partition, then bind your /dev /proc and /sys directories into it, then chroot into it using then use then i would run

reinstall grub?

You have to create an initrd if you switch to the generic kernel after installation.

Is this true of Slackware ?.
Sounds like it should be reported if so. The building of the initrd should be totally independent of boot-loader. I always install to the (root) partition of a new system to avoid stupidity like this, but I don't expect it of Pat.
Might be time I had another look at Slack ...

If editing grub didn't work, then you probably didn't get something right in the entry. On any dual boot machine I've used with slack that had Grub already I just used grub. I've never tried to have grub add slack (or any other distro for that matter) on it's own after the initial install because it's always been trivial task to add an entry. This may not be true of Grub2 if that's what you are using.

I wouldn't think there would be any need for an initrd unless you kernel configuration would require it to boot. I may be wrong.

There is no initrd step in the installer by default. It is done after first booting with the huge kernel by running the command which you specify the options for.

Yes, I just saw that in the notes. I've got a torrent going anyway - I haven't looked at Slack for a while.

since you're running ubuntu 10.04 i am going to assume that you're using grub2 as your loader, that makes things difficult because it is heavily integrated into the OS it's self, i'd probably suggest installing grub legacy as it is much more nerd friendly for multiboot environments.