0khunpocho, примените
твик реестра
Код:

Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\.mht]
@="mhtmlfile"
"Content Type"="message/rfc822"
[HKEY_CLASSES_ROOT\.mht\PersistentHandler]
@="{5645C8C1-E277-11CF-8FDA-00AA00A14F93}"
[HKEY_CLASSES_ROOT\.mhtml]
@="mhtmlfile"
"Content Type"="message/rfc822"
[HKEY_CLASSES_ROOT\.mhtml\PersistentHandler]
@="{5645C8C1-E277-11CF-8FDA-00AA00A14F93}"
[-HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.mht\UserChoice]
[-HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.mhtml\UserChoice]