HELP Getting an "unknown file system" error when starting PC

[Friek555^]

When I was trying to divide my SD card into two partitions yesterday, I accidentally meddled with the partitions on my hard drive. I have got one main partition with practically all my data and Windows 7 on it and a smaller partition with ubuntu 10.04 on it. While the changes I had made were being applied, it froze and I had to cancel the Partition Wizard. Now I have two problems:

1. The partition on the SD card that I had originally declared als Primary in Ext3 format came out as Logical somehow (smaller problem)

2. I had in fact (and in my idiocy, yeah I know I'm stoopid) told the Partition wizard to wipe my linux partition. The computer still worked fine on Windows 7, but when I tried to start it up again today, it only showed me an error directly under the system monitor screen, without having entered the GRUB Menu as it usually did:

error: unknown file system
grub rescue>: _

I can input some unix commands as it seems, but I don't know anything at all about unix.
Can you please help me fix this? I am no Linux or unix expert, I don't know anything at all about grub, I just want to start Windows from the untouched partition on my HDD.

Please note:
some forum entries I found elsewhere told me to type in ls (which apparently shows the partitions available) and then try ls + the name of each partition. ls gave me the list (hd0) (hd0,msdos5) (hd0,msdos1) (fd0).
I tried ls (hd0)/, ls (hd0,msdos5)/ etc. For the other forum users, this had worked and one of the partions had showed their data, but for me, all the hd0 entries showed error: unknown file system again and fd0 showed error: fd0 read error.

When I went into the bios before the system monitor started, it told me something about it not having found a Bios file (WTF?) and only gave me the options to restart the system or cancel the bios.



 

[antoainb]

This happent to me a few months ago. You need to fix the MBR. I reccomend you watch this video:

 

[Guest]

I think something really bad happened here. Grub is your main thingy, bootloader or whatever, and since it is your main bootloader, the first thing it wants to boot in is linux. You wiped your linux, so there is nothing there, but before that, your primary partition for linux or EXT3 came out as logical, and i believe that is why the unknown file system error is happening....

 

Or you just succeded in wiping out everything that was ever in your hard drive in the first place, so BIOS is not found... I'm not sure, im researching abit now, but I will somehow help you, and i know it

[Guest]

Try this video... 

 

Or just repair the windows bootloader....

[Guest]

If you're too bored to watch the video, try these commands:
 

setboot=(hd0,msdos5)
 

then

set prefix=(hd0,msdos5)/boot/grub

 

then

 

insmod normal

then

normal

 

If that doesn't work, replace all the fives with ones! 

[Friek555^]

Great Thanks and Kudos to both of you for the very quick replies. Unfortunately, the set boot/prefix/insmod normal commands didn't work, so I had to ask a friend to make a boot-repair-disc.
If anyone out there has this problem aswell, check out the video antoainb posted, that worked for me. Just be sure that your two PCs have the same version of Windows. I tried to fix my Windows 7 Home Premium 64bit PC using a disc made on a Windows 7 Ultimate 32bit PC first and that didn't work.