I think i have found out what causes this problem, i just ran a Spybot SD scan with latest updates & it found something called Brainbuster Brainbot, when i expanded the branch i saw it mentioned activeskin, so to test it i told spybot to fix it, then i ran avast & got the same error the original poster got.
Installation error: usiGetSkin failed!
I then tried to restore using spybot's recovery option & still got the error, so i then rebooted & then did a repair on Avast & that fixed it
Here is the entries from spybots log
--- Report generated: 2004-10-01 03:36 ---
Brainbuster brainbot: Root class (Registry key, fixed)
HKEY_CLASSES_ROOT\ActiveSkin4.Skin
Brainbuster brainbot: Root class (Registry key, fixed)
HKEY_CLASSES_ROOT\ActiveSkin4.Skin.1
Brainbuster brainbot: Class ID (Registry key, fixed)
HKEY_CLASSES_ROOT\CLSID\{0944D16C-D0F4-4389-982A-A085595A9EB3}
Brainbuster brainbot: Root class (Registry key, fixed)
HKEY_CLASSES_ROOT\ActiveSkin4.SkinLabel
Brainbuster brainbot: Root class (Registry key, fixed)
HKEY_CLASSES_ROOT\ActiveSkin4.SkinLabel.1
Brainbuster brainbot: Class ID (Registry key, fixed)
HKEY_CLASSES_ROOT\CLSID\{5954EA75-9BFA-461A-BD34-CEA3A861FF19}
Brainbuster brainbot: Settings (Registry key, fixed)
HKEY_CLASSES_ROOT\Component Categories\{010E0B1F-1A47-4D07-A83F-43A819E39CCF}
Brainbuster brainbot: Settings (Registry key, fixed)
HKEY_CLASSES_ROOT\Interface\{4921908C-7090-4D37-A6B3-FC447F08378A}
Brainbuster brainbot: Settings (Registry key, fixed)
HKEY_CLASSES_ROOT\Interface\{750FC67C-0311-4391-9864-A2EFED49BD28}
Brainbuster brainbot: Settings (Registry key, fixed)
HKEY_CLASSES_ROOT\Interface\{F3FC950C-7583-4377-BAD8-EFBEAA33273C}
Brainbuster brainbot: Settings (Registry key, fixed)
HKEY_CLASSES_ROOT\TypeLib\{90F3D7B3-92E7-44BA-B444-6A8E2A3BC375}
Did Volaris run spybot in the past couple of days?
Seems spybot gets a false positive on this, im pretty sure it is spybot, but i also run prevX home & got the latest updates for that as well, Just out of curiosity, does Volaris run PrevX as well?
If it is spybots fault, it might be an idea for Avast team to notify Spybots makers about it
Hope this helps
BaNzI