First time poster here. Got the same problem as mystifeid, except all the fixes listed haven't worked for me. Here is my info if it's any help:
WindowBlinds version : WindowBlinds 6.4 (build 73 x86)
WindowBlinds is installed correctly on this PC
WindowBlinds appears to be activated on this PC
Your machine supports per pixel borders on WindowBlinds skins.
(SyncMaster 2253BW/2253LW,SyncMaster Magic CX2253BW/CX2253LW(Digital)) 1 is attached to NVIDIA GeForce 9800 GTX+
Wblind.dll 2009/02/06 10:45:20
Wbsrv.dll 2009/02/05 13:39:58
Wbconfig.exe 2009/02/10 13:13:20
Wbload.exe 2008/04/26 15:14:14
Wbhelp.dll 2008/04/26 15:14:07
Wbui.dll 2008/04/26 15:14:05
Tray.dll 2008/04/26 15:14:21
Screen.exe 2008/07/15 10:31:09
I've tried a fresh install (using a registry cleaner), disabling my anti-virus before an install, making exceptions to Windowblinds with my anti-virus program, disabling several services (including the Nvidia one) and I'm actually in the process of working this out with Stardocks support staff. Sadly, they are at a loss as to why my skins revert back to Classic after a reboot. So I thought I'd try here. My OS is XP SP3/32-bit and I've never had a previous version of Windowblinds on my system.
As an added note, nothing pertaining to Windowblinds shows up in the "Services" tab of the Configuration Utility. Any and all help will be appreciated.