How to restore my scounix5.0 system?

It seems that  your disk has a big problem;
if isn't a physical problem (replace in this case) , you should repair with a previous hard backup (if you have done it), booting floppy or other bootable disk

first, some explanation:
the disk named hd00 represent the whole disk (the principal; secondary should be hd10), and containing:

     1 track (size depending of type of disk) for the partition table, boot, label...
     1 or more partitions (fdisk); at least 1 active partition: hd0a (a means active) containing:
          1 cylinder for the table of division (particularity SCO) that you can read with divvy
          1 or more division (at least the root named generally /dev/root)


example of a division table
# divvy (command that gives the SCO division of a partition: hd0a for the active partition)
+---------------+---------------+--------+---+-------------+------------+
| Name          | Type          | New FS | # | First Block | Last Block |
+---------------+---------------+--------+---+-------------+------------+
| hd0root       | EAFS          |  no    | 0 |            0|       99999|
| swap          | NON FS        |  no    | 1 |       100000|      195999|
| users         | EAFS          |  no    | 2 |       196000|      663999|
| oracle        | EAFS          |  no    | 3 |       664000|      899999|
| images        | EAFS          |  no    | 4 |       900000|     1022964|
|               | NOT USED      |  no    | 5 |            -|           -|
| recover       | NON FS        |  no    | 6 |      1022965|     1022974|
| d1057all      | WHOLE DISK    |  no    | 7 |            0|     1029103|
+---------------+---------------+--------+---+-------------+------------+
1028095 1K blocks for divisions, 1008 1K blocks reserved for the system

 n[ame]       Name or rename a division.
 c[reate]     Create a new file system on this division.
 t[ype]       Select or change filesystem type on new filesystems.
 p[revent]    Prevent a new file system from being created on this division.
 s[tart]      Start a division on a different block.
 e[nd]        End a division on a different block.
 r[estore]    Restore the original division table.


NOW, i suggest you:
1° boot from an other support (floppy, or other bootable device) (installing SCO propose to make two diskettes boot and root: put boot, power on, and read instructions)
2° with commands fdisk, and divvy, try to determine where is the problem (seem in /dev/root: 1st division of hd0a)
3° if you have to do, try to save the most information using
     fsck -y to try cleaning maximum of informations
     mount anywhere (/mnt) the ill division using the -r (readonly option) if necessary
     save the informations with a cpio command (not dd)
4° use the command badtrk that can reallocate bad blocks on a division,
5° erase the filesystem using mkfs (not efficient in case of bad block remaining)
6° restore yours data (from earlier backup if has been done (?)), and the cpio of 3° for recent files

I WISH YOU A LOT OF LUCK
generaly, blocks that could not be read is synonim of partially crashed disk
so is better to save what you can, replace the disk, re-install SCO and restore some data.

I had a similar problem on an old PC with a recent disk not known in the setup, and it has been necessary to describe cylinders, tracks, heads to the setup (you find the characteristics on the disk)....
perhaps you can verify this first.

;-)

   Thank you very much for your help!  
    When I use my boot floppy to boot my sco,the boot floppy is normal,but when I insert root filesystem floppy,at first it is normal too,but in the end there are a lot of error:
   Notice :HTFS£ºOut of inodes on EAFS dev ram (31/7)
   INIT:failed write of utmp entry:""
   INIT SINGLE USER MODE
   INITSH /bin/sulogin:not found
   INIT:New run level:2

 and then it stop here.

Can you tell me why?  Thank you very much!!!

I have made a booting floppy and root filesystem floppy when I install my sco unix system ,but I don't know how to use it to restore my system,Can you tell me more about how to use booting  floppy,or give me some ip address about it?

IMPORTANT: You should **NOT** write-protect your root filesystem floopy!

Boot using your boot floopy, insert root filesystem floopy (do not write protect). You will be as root in # prompt.

Now, run fsck -y /dev/root
if root filesystem is HTFS, run fsck -o full /dev/root

Repeat the same for all other filesystems. Once you complete this step, shutdown the system by
cd /
sync
uadmin 2 0     ( or use haltsys command)

Remove the floopy disk and reboot the machine.

Do not go to multiuser mode. i.e. do not press CTRL D to go to multiuser more. Enter your root passwd here. You will reach # prompt.

Run fsck on all other filesystems and try mounting them. otherwise tell us what are the fs you have.
PS: Do not run fsck again on root filesystem.
Hope this helps.

  I can not go to # prompt.
   When I use my boot floppy to boot my sco,the boot floppy is normal,but when I insert root filesystem floppy(I DON NOT write-protect your root filesystem floopy) ,at first it is normal too,but in the end there are a lot of error:
   Notice :HTFS£ºOut of inodes on EAFS dev ram (31/7)
   INIT:failed write of utmp entry:""
   INIT SINGLE USER MODE
   INITSH /bin/sulogin:not found
   INIT:New run level:2
   and then it stop here
   Can you tell me more about how to use booting  floppy to restore my system,If I do not make a booting floppy,How can I enter my system?How to use booting floppy to enter my system?
    Thank you!!!

  I can not go to # prompt.
   When I use my boot floppy to boot my sco,the boot floppy is normal,but when I insert root filesystem floppy(I DON NOT write-protect your root filesystem floopy) ,at first it is normal too,but in the end there are a lot of error:
   Notice :HTFS£ºOut of inodes on EAFS dev ram (31/7)
   INIT:failed write of utmp entry:""
   INIT SINGLE USER MODE
   INITSH /bin/sulogin:not found
   INIT:New run level:2
   and then it stop here
   Can you tell me more about how to use booting  floppy to restore my system,If I do not make a booting floppy,How can I enter my system?How to use booting floppy to enter my system?
    Thank you!!!

It seems to me now that is not possible to solve your problem  

Your root floppy is perhaps corrupted, or realized with an oldier version ??

two solutions now:
1) use an other diskette make by mkdev floppy on a similar system
2) or reinstall a system with the prevent option of the divvy command on the divisions you want to preserve for overwriting; (you must know beginnings and endings of actual divisions)

Do you have the original SCO Openserver Disks?
Did you machine memory check go okay?

I have the original SCO Openserver Disks,
My machine memory check okoy

Use the original boot disk .
At the boot prompt type "tools".
After the system boot you should be able to do the fsck of /dev/root as stated on
previous messages.

If this does not work contact someone from SCO or someone near you that is used to
give SCO technical support.
If you have reliable backups of everything then just reinstall the system and restore
the data.

I assume you do not need BTLD for you primary disk controller.

To check root and boot filesystems use the following commands:
fsck -ofull /dev/hd0root
fsck -ofull /dev/boot

To mount,
mount /dev/hd0root /mnt

To shutdown, umount /mnt and shutdown or haltsys.
Try booting now.