I have been running a windows 2000 installation which worked fine until vbox updated early this week. If the CPU did not support virualization, why did it work?
I am not sure, looking at your cpu flags I can't see a reference to virtualization.
Failed to open a session for the virtual machine XP_64.
Unsupported version 11 of data unit 'vga' (instance #0, pass 0xffffffff) (VERR_SSM_UNSUPPORTED_DATA_UNIT_VERSION).
Result Code: NS_ERROR_FAILURE (0x80004005)
Component: Console
Interface: IConsole {8ab7c520-2442-4b66-8d74-4ff1e195d2b6}
This is the error on my 64 bit PC, after the same update.
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 75
model name : AMD Athlon 64 X2 Dual Core Processor 5000+
stepping : 2
microcode : 0x62
cpu MHz : 1000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow rep_good nopl extd_apicid pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy vmmcall
bogomips : 1995.81
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: ts fid vid ttp tm stc
processor : 1
vendor_id : AuthenticAMD
cpu family : 15
model : 75
model name : AMD Athlon 64 X2 Dual Core Processor 5000+
stepping : 2
microcode : 0x62
cpu MHz : 1000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow rep_good nopl extd_apicid pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy vmmcall
bogomips : 1995.81
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: ts fid vid ttp tm stc
Thank you. Discarding the saved state worked, but the older pc I use at work to keep a ms access database. By chance, I backed up the .vdi the last day it worked so I may be able to migrate it to another PC. I don,t really have the luxury of time.
Don't thank me, thank Google

It comes full circle.That's where I started!
Happy day! Discarded saved state & I am back in business.