[Offer] Microsoft MS-DOS 3.20 (non OEM) [5.25] (IMG)

callmejack

Surprisingly, this non OEM version is not present on Winworldpc. It's apparently the first version of MS-DOS that Microsoft sold directly to end-users.

https://mega.nz/file/KW4k3IAb#QoYIlAEy9dv_bVZWfsRCBCrMvunCVBl69xcOnATCofs

ibmpc5150

Wow, thanks very much!
I also have it and posted it as screenshot and file listing ago.

https://forum.winworldpc.com/discussion/comment/160090#Comment_160090

But would you please dump it again by SCP from Track 0 to 41?
Because hidden data for MS Genuine is included on both track 40

This is Microsoft DOS Genuine version, not distinguished as OEM or Retail version before released version 5.0x.

Microsoft didn't allow to sell it as Retail Package without NEW PC.

callmejack

@ibmpc5150 That's interesting, I didn't know Microsoft was writing some hidden data in their DOS disks in order to detect non genuine copies. Was it serialized so that they could identify the original buyer or just the same generic data on all copies ?

I include the file as an attachment.

ibmpc5150

Thanks, would you please dump disk 2 of SCP (Track 0-41) too?

I've checked disk 1 of both mine and yours.


1) My track 40 of disk 1 (Created on 07/11/1986)


2) My track 40 of disk 2 (Created on 07/10/1986)


3) Your track 40 of disk 1 (Created on 02/28/1987)

SomeGuy

That is mastering data. Most professional mastering systems write something like that after the last data track. It includes things like the time the disk was written, the duplicator's serial or ID number, the title of the disk image, and so on.

Its primary use was diagnostic. If a store got a batch of faulty disks, they could use that information to track down the problematic duplicator.

These days collectors use it to help prove "authenticity" of a dumped disk. For example, if is is missing or contains a kryoflux signature then that may mean someone modified the content and tried to pass it off as authentic. (Imaging someone trying to find some rare revision of a game disk that sells for $absurdamount on eBeh.)

Personally, I think its use is overrated, but it is important to dump all physical tracks as any kind of data can be stored there. Copy protection can hide there, and user data disks may have been re-formatted to greater capacities (like 420k on a 360k disk) that include these extra tracks to store normal data.

Unless a title is copy protected, I may or may not include flux dumps in the library, but I encourage submitting complete flux dumps (SCP, KF RAW) as it sometimes happens it is not always obvious when a title is copy protected.

callmejack

Unfortunately disk 2 is damaged, I had a problem with my floppy drive and it trashed the disk

ibmpc5150

@callmejack

Oops, that's too bad. Sorry for inconvenience.

callmejack

That’s ok, I need to find a more reliable floppy drive, I’ve had several problems with this one.

DeFacto

>This is Microsoft DOS Genuine version, not distinguished as OEM or Retail version before released version 5.0x.
>Microsoft didn't allow to sell it as Retail Package without NEW PC.

Indeed. This generic package was meant for smaller system builders who couldn't bother with the full OEM Adaptation Kit (OAK) like the larger OEMs did. It was still sold along with a computer, never standalone (not legally, anyway).