stop ms-dos 6 running auto scandisk on fat

[Rigo]

I need to disable the auto scan as it messes up the file system on a clone I'm trying to use to replace a bad sectors ridden drive.
The new drive has larger capacity than the original.

 

[backwoodsman]

I need to disable the auto scan as it messes up the file system on a clone I'm trying to use to replace a bad sectors ridden drive.

No doubt I could've told you more if you'd asked 25 years ago. But at this late date, the only thing that springs to mind is, if you can't find what's making it run automatically, maybe it would work to rename chkdsk.exe to something else, like chkdsk1.exe. That way it won't find it, but you'll still have it there if you need it. But...

The new drive has larger capacity than the original.

Capacity shouldn't matter; if chkdsk is trashing the filesystem, it likely has something to do with a different cylinders/heads/sectors configuration than the original. Systems of that era were very sensitive to that; when moving a drive you had to be very careful to match exactly the parameters used when the drive was formatted. If it's IDE the drive itself didn't care -- most would auto-translate whatever parms you gave them to their own physical configuration -- but if they're different it confuses the OS. In that case any disk writes would likely trash the filesystem.

I'd suggest reformatting the drive using the same cyl/hd/sec parms as the original drive. If you don't need the extra capacity it should work fine that way. If you do need the capacity, you could try increasing the cylinders while keeping heads & sectors the same; that would have a good chance of working. Of course all this assumes I'm accurately remembering all that stone-age stuff, which I haven't thought about since sometime in the '90s.

 

[phaZed]

If it's MSDOS 6.x - There is no "dirty bit" flag in the FS. It simply checks if the system shut down cleanly or not.

You should be able to look in autoexec.bat and REM the CHKDSK /F line.

 

[NETWizz]

If it's MSDOS 6.x - There is no "dirty bit" flag in the FS. It simply checks if the system shut down cleanly or not.

You should be able to look in autoexec.bat and REM the CHKDSK /F line.

No chkdsk as far as I know it is ScanDisk

If you never want ScanDisk to run, what if you rename the .exe for it to something else, so the OS cannot find it?

 

[phaZed]

No chkdsk as far as I know it is ScanDisk

Almost certainly correct!

 

[backwoodsman]

No chkdsk as far as I know it is ScanDisk

Scandisk started with MS-DOS 6.2; before that it was chkdsk. Regardless, my comments above about hard disk geometry possibly being the problem still apply either way.

 

[YeOldeStonecat]

chkdsk continued all the way up to the end of Windows ME (the last Windows based on the dos sub system)
Scandisk came along with dos 6.2 and co-existed with chkdsk all the way to the end...but it was much better to run scandisk once it came out.

 

[Philippe]

Look for the line "Autoscan" in "Scandisk.ini" and change it to "autoscan=0".

 

[timeshifter]

disable the auto scan

when does the auto scan take place? On boot up?

I was thinking of it happening when you insert a USB disk. But it's DOS. Things aren't lining up in my brain.

 

[Rigo]

Thank you all folks for the different inputs.
I've now returned the computer and won't be able to try the suggestions.
The computer is for an auto mechanic shop and only runs a only program called DYNO TUNE which automatically launches at startup.
Socket 7 with Pentium. Of course, there's no installation package.
We sourced out a replacement motherboard as the original had a problem with the graphics at the motherboard level. I have a collection of graphics card of the era and none worked until we replaced the motherboard.
Some functions in the DYNO program had some glitches which probably had to do with bad sectors on the 2GB IDE drive.
Imaging the drive to other now larger capacity drives always indicated 8 unrecoverable errors which probably triggered the autoscan that tried to correct the filesystem thus messing up the system after the first successful booting.
Converted SATA drives not accepted.

 

[timeshifter]

I’ve never used one, but I’m aware that they make IDE to SD card adapters. Maybe that’s a solution if you’re having trouble with old hard drives.

 

[nlinecomputers]

They need a new pc. That DOS program would probably run just fine on win 11. But if it doesn’t you can convert the drive into a VM. Running on old 90s hardware is just crazy.

 

[Philippe]

I’ve never used one, but I’m aware that they make IDE to SD

They work real good. It's like an SSD for an old PC. (IDE to CompactFlash, or directly from an ISA slot to a CompactFlash card).

 

[Rigo]

I’ve never used one, but I’m aware that they make IDE to SD card adapters. Maybe that’s a solution if you’re having trouble with old hard drives.

I've done that for an NT4 system and it worked, the DOS one no

 

[Rigo]

They need a new pc. That DOS program would probably run just fine on win 11. But if it doesn’t you can convert the drive into a VM. Running on old 90s hardware is just crazy.

The biggest problems are that there's no installation media for the software that they need, some files from that software have been affected by the bad sectors and should be replaced/repaired otherwise the glitches would just transfer.