Rafael Rivera, the same expert Windows hacker that figured out how to customise your Windows 7 logon background, finds another hack that changes the UI to look better with darker background images.
The change is simple enough—just have to roll up your sleeves and apply a simple registry hack—but could make a big difference if you've already customised your logon wallpaper. To make the change, open up the registry editor and browse down to the following key:
Create a new DWORD called ButtonSet and give it a value between 0-2 (You'll want to use 2 for darker backgrounds). You can delete the key or set it to 0 to revert back to the default setting, and the changes should be applied immediately.
Hit the link for Rafael's full explanation of the registry values and what they do. If you aren't sure how to change the logon wallpaper in the first place, we've previously covered how to use Logon Changer to customise the background image. Readers using XP or Vista can use LogonStudio to customise the background, but there's no registry hack for the buttons.
Tweak your Windows 7 Logon UI "button set" [Within Windows]