REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail]
@="Imp"

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp]
@="IMP"

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\Protocols]

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\Protocols\mailto]
"EditFlags"=hex:02,00,00,00
"URL Protocol"=""
@="URL:MailTo Protocol"

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\Protocols\mailto\shell]

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\Protocols\mailto\shell\open]

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\Protocols\mailto\shell\open\command]
@="iexplore.exe -nohome webmail.example.com/horde/imp?action=compose&to=%1"

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\shell]

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\shell\open]

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail\Imp\shell\open\command]
@="iexplore.exe -nohome webmail.example.com/horde/imp"
