usbdrive,
Сверьте со здоровой системой разделы и их подразделы соответственно:
Код:

HKEY_CLASSES_ROOT\SystemFileAssociations\.lnk
HKEY_CLASSES_ROOT\SystemFileAssociations\.exe
HKEY_CLASSES_ROOT\SystemFileAssociations\.reg
HKEY_CLASSES_ROOT\SystemFileAssociations\.LST
HKEY_CLASSES_ROOT\SystemFileAssociations\.TXT
HKEY_CLASSES_ROOT\SystemFileAssociations\.cmd
HKEY_CLASSES_ROOT\SystemFileAssociations\.vbs
HKEY_CURRENT_USER\Software\Classes\.cmd
HKEY_CURRENT_USER\Software\Classes\.TXT
HKEY_CURRENT_USER\Software\Classes\.LST
HKEY_CURRENT_USER\Software\Classes\.lnk
HKEY_CURRENT_USER\Software\Classes\.reg
HKEY_CURRENT_USER\Software\Classes\.vbs
HKEY_CURRENT_USER\Software\Classes\Drive\shellex\FolderExtensions
HKEY_CURRENT_USER\Software\Classes\SystemFileAssociations\.lnk
HKEY_CURRENT_USER\Software\Classes\*
HKEY_CURRENT_USER\Software\Classes\Applications\7z.exe
HKEY_CURRENT_USER\Software\Classes\Applications\7zFM.exe
HKEY_CURRENT_USER\Software\Classes\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}
HKEY_CURRENT_USER\Software\Classes\CLSID\{B41DB860-8EE4-11D2-9906-E49FADC173CA}
HKEY_CURRENT_USER\Software\Classes\Folder
HKEY_CURRENT_USER\Software\Classes\.EXE
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.exe