Can't start vm after moving to new host

[hangerglide]

I moved my vbox setup to a new host. I have all the files from the original host.

But I can't get one important windows 7 pro vm to start. It was originally created with vbox 3, so it had it's files in two folders, one for the vm config and one for the media (went through that above). I've tried to follow the pattern that has worked for other vms but the vm fails to boot - windows 7 starts and then crashes, offers to try to fix itself and fails.

What I did (same pattern as has worked for other vms) is to start creating the vm, and at the step when it's asking for a media file, I copy the old vdi file to the just created folder for the new vm. I tell vbox to use that as the hard disk. At first it says the disk is inaccessible but by the time I've completed the new vm wizard it says 'normal'. But the vm won't boot. It's not using IO-APIC, and none of the other machines that use vdi files are either.

Windows seems to start, shows a "windows is loading files" message, then goes back to the vbox initial startup screen, and shows windows again with the option to repair or start normally. Start normally repeats the cycle. Repair takes a long time and does not succeed.

I've attached the log file. vbox 4.3.6.

Note, this issue was raised in another thread (viewtopic.php?f=6&t=57635) and the extremely helpful mpack asked me to start a new thread for this issue.

Since my original posting I've found that other vbox 3.x machines that I try to start on the new host fail in the same manner. I thought the pattern above ("What I did...") was what mpack suggested might work for migrations like this, but I must be missing something.

[mpack]

I don't understand one thing: the other thread was in large part about converting a v3 VM to v4 layout - necessary before backups become practical. But, surely you did all that long ago, and all VMs - and backups of VMs - are in v4 format? If the backup is in v4 format then restoring from a backup should be very easy: just copy files back, and perhaps use Machine|Add if the VM isn't already still registered.

On a separate note, it would be highly unusual to have a 64bit Win7 VM that didn't use IO APIC. The latter is in the default template for Win7-64.

[hangerglide]

Thanks for your input. All of the vms were 'running' in 4.x vbox; probably that means all were converted to 4.x? But because some of the vms were created in 3.x, the config info and the hdd file were in separate folders.

There is a great deal I don't understand about vbox, so I could easily be making this more difficult than it needs to be.

#1 Would you expect the steps I took to result in a working vm?

#2 The files that I had before, and which worked, were like this:
config folder contains: windows 7 pro x64 base.xml
hdd folder contains: windows 7 pro x64 base.vdi

If it is possible to 'add' or import those files without the steps I mentioned in the starting post, that'd be fine.

I have tried to 'add' the xml file and I get the kind of error like this:

Failed to open virtual machine located in E:/virtualbox/msmachines/win 7 pro x64 base/windows 7 pro x64 base.xml.
Could not find an open hard disk with UUID {28c445a2-2d4d-457a-b22b-75ec7f73f3f9}.
Result Code: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)
Component: VirtualBox
Interface: IVirtualBox {fafa4e17-1ee2-4905-a10e-fe7c18bf5554}

The Add wizard ends then, with no vm created. If there is a way to make it work that would be great.

So between my #1 and #2 the question is, which is a valid set of steps to recover vms like these?

[mpack]

Thanks for your input. All of the vms were 'running' in 4.x vbox; probably that means all were converted to 4.x?

No, VirtualBox is backwards compatible. When v4 came out it didn't just break everyone's VMs, or even make big changes to them - instead it continued to use them as they are, and that is what it still does. Unfortunately the v3 format VM is very difficult to back up, because you need to copy a piece from this folder, a piece from that folder, and a few lines from VirtualBox.xml. That's why I suggested to you last time that you converted all your VMs to v4 format asap.

In the case of an XP VM, you can recover somewhat by building a new VM around the existing VDI, and that might have allowed you to struggle on. Win7 however is more complicated because it has a boot manager which might care about disk UUID changes, and the activation feature will certainly care about motherboard signature changes - which happens when the VM-UUID changes because you created a new VM.

If you have a v3 xml then you can't just add it. There are no steps guaranteed to make it work. You have no choice but to create a new VM. But, I would turn IO APIC on and see if that works. I would build a Win7 VM around your VDI, using the default Win7-64 template settings, and if it doesn't boot right away I'd try a "repair installation" on it using the Win7 setup DVD.

[hangerglide]

Now I understand better...I'd not differentiated between converting to v4 and backwards compatible. My old vms were never converted. I guess I won't be able to do it since the old host pc crashed.

With your last recommendation, re building a win 7 vm around the vdi I have, is that process any different than what I described as the steps I've tried to get it to work?

I have switched on IO APIC, it didn't help.

The repair that I can choose during the failed boot does not ask for a windows dvd...is there something special I can try to get it to do so, and might it help (where the current repair is failing)?

[mpack]

Remember that VirtualBox is mostly agnostic about the OS you choose to run inside the black box, so if your basic recovery procedure is enough to satisfy VirtualBox (basically, same hardware recipe and all files in their proper folders) then it should be easy to create a new VM which at least attempts to boot Win7. Then it's just a matter of dealing with whatever complaint Win7 itself has.

I'm assuming btw that this VM never used snapshots, because a V3 VM which used snapshots would require extra steps to recover.

By "repair the installation" I mean boot up with the Win7 setup DVD and select "Repair". I've done this with an XP machine, never Win7, but I assume the feature is there.