Amstrad 1640

[Swerv]

Hi,
I am trying so set up the above VM. I have the 4 .img files.
I set up A vm in version 7.0.10 under operating systems "other & DOS" with a 20Mb hard drive.
Disk 1 is loaded and the system boots. I then fdisk the HD & use all of it for the partition. I reboot from A:, then use format c: /s. I then get the error:-

Format complete
System transferred

Error reading partition table
Format failure

I then remove disk a and attempt to boot from c:, but all I get is a blank screen with a flashing underscore _

Any help would be appreciated, I did successfully do this years back, but it may have been under version 5 of virtualbox. I was wondering if things have changed over time!

[mpack]

Please provide a VM log file. Make sure the VM is fully shut down, then right click it in the manager UI. Select "Show Log" and save "VBox.log" (no other file) to a zip file. Attach the zip here.

[Swerv]

Hi,
Thanks for the quick reply.
Attached is the log.

[Swerv]

I have figured it out! By default vbox creates .vdi harddisk, I need to convert it to .vdh harddisk. Boy, wish I had found that out earlier, would have saved about 2 days work.

[mpack]

I have figured it out! By default vbox creates .vdi harddisk, I need to convert it to .vdh harddisk.

? No, you didn't need to do that. The guest OS has no way of knowing what host container format you used, so it certainly can't be affected by the choice.

But, one thing that converting to VHD might do is clear up any minor inconsistencies in the header. The guest OS is not involved. But that would mean that any conversion would do, and you could now convert it back to VDI and it should still work.

[Swerv]

Many thanks for taking the time to look at this. I don't think I will take the chance to convert it back though, now it is working.
BTW, was there anything in the log file that pointed to this?

[mpack]

I wanted the log in order to check for common errors when dealing with DOS era guests - making the disks too large or giving the VM more RAM than it knows how to handle. I didn't see any errors like that in your log, and in any case you had already reported that the VM was now working.

[Swerv]

I have figured it out! By default vbox creates .vdi harddisk, I need to convert it to .vdh harddisk.

you could now convert it back to VDI and it should still work.

I just converted it back to .VDI and it all worked. So there is something about the default of making the first .VDI that is not working correctly. So it does seem to matter (at least in DOS machines) weather you start with VDI or VHD.

Thanks again for your help.

[mpack]

So it does seem to matter (at least in DOS machines) weather you start with VDI or VHD.

I don't know how you drew that conclusion now that you have a working VDI. The correct conclusion is that using any defective disk image can cause problems in and out of the guest OS. It doesn't matter if the defective image is VDI or VHD.

But, we don't recommend VHD as it is more error prone and not the native format in VirtualBox. I don't know what procedure you used to create your original VDI or why that procedure had defective results.

[Swerv]

So it does seem to matter (at least in DOS machines) weather you start with VDI or VHD.

I don't know how you drew that conclusion now that you have a working VDI.

I have drawn that conclusion because I have tried multiple times setting with the default VDI when creating a new machine, & each time it fails at the same place. When a new machine is created without a Hard disk, & a VHD is manually added to it, it succeeds every time. It is strange though that converting it back to VDI from VDH worked. I must admit that I have not tried manually adding a VDI after creating the machine, that I will try. But, letting Virtualbox create a new machine, using the default VDI does cause this problem. I am sure in pervious versions of VB, it gave you a choice of what type of disk you wanted to create when selecting a new machine, but now it does not.