this was tested on: Linux laptop (Core2Duo T2050) 3.16.0-4-686-pae #1 SMP Debian 3.16.7-ckt11-1 (2015-05-24) i686 GNU/Linux

apt-get install linux-headers-$(uname -r); # install linux header files
aptitude update; # aptitude can resolve conflicts better than apt alone
aptitude install libssl0.9.8 libpython2.6; # install missing libraries

wget http://download.virtualbox.org/virtualbox/5.0.12/virtualbox-5.0_5.0.12-104815~Debian~squeeze_i386.deb; # download virtualbox for squeeze package

dpkg -i virtualbox-5.0_5.0.12-104815~Debian~squeeze_i386.deb; # install

# you should now wait a little for the recompilation of your virtualbox kernel modules

# when running

ps uax|grep make

# i get

make --no-print-directory install
make KBUILD_VERBOSE=1 SUBDIRS=/tmp/vbox.0 SRCROOT=/tmp/vbox.0 CONFIG_MODULE_SIG= -C /lib/modules/3.16.0-4-686-pae/build modules

make -C /usr/src/linux-headers-3.16.0-4-common O=/usr/src/linux-headers-3.16.0-4-686-pae modules

/bin/sh -c make -C /usr/src/linux-headers-3.16.0-4-686-pae \ KBUILD_SRC=/usr/src/linux-headers-3.16.0-4-common \ KBUILD_EXTMOD="/tmp/vbox.0" -f /usr/src/linux-headers-3.16.0-4-common/Makefile \ modules

make -C /usr/src/linux-headers-3.16.0-4-686-pae KBUILD_SRC=/usr/src/linux-headers-3.16.0-4-common KBUILD_EXTMOD=/tmp/vbox.0 -f /usr/src/linux-headers-3.16.0-4-common/Makefile modules

make -f /usr/src/linux-headers-3.16.0-4-common/scripts/Makefile.build obj=/tmp/vbox.0

# this means it worked

Starting VirtualBox kernel modules ...done.

# exit root shell and become your default user then type

virtualbox

# and you should get the gui console

virtualbox installed on squeeze core2duo

always go for VDI harddisk format… anything else will cause errors and is not (really) supported.

virtualbox always use vdi harddisk images

the cpu is a 15 year old laptop with a Core2Duo

cat /proc/cpuinfo 
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 14
model name	: Genuine Intel(R) CPU           T2050  @ 1.60GHz
stepping	: 8
microcode	: 0x39
cpu MHz		: 800.000
cache size	: 2048 KB
physical id	: 0
siblings	: 2
core id		: 0
cpu cores	: 2
apicid		: 0
initial apicid	: 0
fdiv_bug	: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 10
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc arch_perfmon bts aperfmperf pni monitor est tm2 xtpr pdcm dtherm
bogomips	: 3192.39
clflush size	: 64
cache_alignment	: 64
address sizes	: 32 bits physical, 32 bits virtual
power management:

processor	: 1
vendor_id	: GenuineIntel
cpu family	: 6
model		: 14
model name	: Genuine Intel(R) CPU           T2050  @ 1.60GHz
stepping	: 8
microcode	: 0x39
cpu MHz		: 1600.000
cache size	: 2048 KB
physical id	: 0
siblings	: 2
core id		: 1
cpu cores	: 2
apicid		: 1
initial apicid	: 1
fdiv_bug	: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 10
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc arch_perfmon bts aperfmperf pni monitor est tm2 xtpr pdcm dtherm
bogomips	: 3192.39
clflush size	: 64
cache_alignment	: 64
address sizes	: 32 bits physical, 32 bits virtual
power management:

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