Guest Windows XP no longer opens after installing Yosemite

[Cash]

Note
Upgraded to Mac OS Yosemite today from Lion. Had been using VirtualBox Windows XP guest for a
couple of years with the Lion OS version. After the OS upgrade, can no longer start Windows XP guest
and it fails with the followng
"A critical error has occurred while running the virtual machine and the machine execution has been stopped."
VirtualBox version is 4.1.23.
Any ideas as to what is wrong and how to correct it?

[loukingjr]

Try updating VirtualBox. You are using a fairly old version. (2 years old).

[Cash]

Please note my original post said "Windows 98". The guest OS is actually "Windows XP"

I have tried upgrading via the Virtual Box "Check for Update" function and it reports that I am already
running the most current version. Checking on virtualbox shows that there are 4.1.x versions up
to 4.1.34. Not sure why it won't offer any options to update.

Can I install a 4.2 or 4.3 version over the top of 4.1?

[loukingjr]

It's better to use the VirtualBox_Uninstall.tool first to uninstall. Then install 4.3.18. You should update the guest additions in XP as well.

[scottgus1]

Please keep in mind that versions from 4.3.14 onward have the new hardening feature for security issues, the developers are still working out the glitches - see the forum stickies up top. 4.3.12 and earlier has the security hole (essentially malware on the host can dig into Virtualbox and get greater permissions than the malware would normally have) but does work well for guests up to Windows 8.1 - keep malware off the host and you'll probably be OK. (I got Windows 8.1 to run on version 4.2.16, and 4.2.16 is what I'm using now for my work guests and the office server, all Windows 7.)

[loukingjr]

Please keep in mind that versions from 4.3.14 onward have the new hardening feature for security issues, the developers are still working out the glitches - see the forum stickies up top. 4.3.12 and earlier has the security hole (essentially malware on the host can dig into Virtualbox and get greater permissions than the malware would normally have) but does work well for guests up to Windows 8.1 - keep malware off the host and you'll probably be OK. (I got Windows 8.1 to run on version 4.2.16, and 4.2.16 is what I'm using now for my work guests and the office server, all Windows 7.)

I was under the impression that the security issues for versions of VirtualBox beyond 4.3.12 only affect installing it on a Windows host. I've had no issues with VirtualBox all the way through 4.3.18 on both Mac and Linux hosts running Windows XP-Windows 10 guests.

[mpack]

I was under the impression that the security issues for versions of VirtualBox beyond 4.3.12 only affect installing it on a Windows host.

That's correct.

@Cash: please provide a VM log file. Minimum information needed for assistance.

As Lou says, I would recommend upgrading to 4.3.12 first - if you aren't prepared to upgrade then any investigation of potential bugs is pointless. We don't want to investigate issues that were already fixed.

[Cash]

I installed 4.3.18 (without uninstalling the previous version) and all appears to be OK.
I was hesitant to uninstall the previous version first as I was not sure how much of
my installation would be removed. (Would it delete the guest OS for example?)

Thanks to all!

[scottgus1]

Ah, Mac host. Gotcha.
Last time I ran a Mac was my dad's old Macintosh Plus (featured as a character in "Bloom County"): a megabyte of memory, 1Mhz Motorola 68000 processor and two - count 'em, two - dual-sided floppy drives, one internal, one external. The usual OS was 400 or so kb - kilobytes - allowing room for another application or two on the same floppy. System 7 took a whole 800kb disk, but the other drive was good for all the other programs we wanted to run. Friend of ours got a 20 megabyte hard drive add-on - yes, "mega" - and we thought he'd never fill it up.
The good ole days...

[loukingjr]

I installed 4.3.18 (without uninstalling the previous version) and all appears to be OK.
I was hesitant to uninstall the previous version first as I was not sure how much of
my installation would be removed. (Would it delete the guest OS for example?)

Thanks to all!

glad it's working. using the uninstall tool does not remove any guests.