La ultima version del dosflash (v1.8 Build 20090808) viene con "portio64.sys" es el driver para 64bits. El problema es que no esta firmado, así que windows de 64bits bloquea rotundamente su instalacion.
Segun pone en el "ReadMe.txt" del dosflash:
Tips for running DosFlash on Windows 7
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Since Windows Vista 64 Bit and upwards it is necessary that every driver is signed. Because
the DosFlash driver will not be signed by MS due to some unknown reason we need to cicumvent
this check. You have the following 2 possibilities to do this.
Safe Way of Disabling Driver Signature Enforcement
1) On Windows 7 bootup press F8 to get to the extended boot options screen
2) Choose "Disable Driver Signature Enforcement"
3) To start DosFlash right click on it in Windows Explorer and choose
"Run as administrator" > answer the message box with "Yes"
4) Short after the program started a "Program Compatibility Assistant" warning message
is displayed, you can simply ignore this by pressing the "Close" button
Recommended Way of Disabling Driver Signature Enforcement
1) Disable User Account Control (UAC)
- go to "Start Menu" > "Control Panel" > "User Accounts and Family Safety" > "User Accounts"
- click on "Change User Account Control settings"
- set the slider bar to the lowest value (Never notify) > click "OK"
2) Sign the DosFlash driver
- download the "Driver Signature Enforcement Overrider" (DSEO) from
http://www.ngohq.com/home.php?page=dseo
- start DSEO > click "Next" > "Yes" > choose "Sign a System File" > "Next" > enter the path to
the used driver (portio32.sys or portio64.sys) > "OK" > "OK"
3) Disable Driver Signature Enforcement
- start DSEO > click "Next" > "Yes" > choose "Enable Test Mode" > "Next" > "OK"
4) Restart the computer
Keep in mind that with the recommended way the changes will have effect on every reboot without
doing anything manual. The first way needs to be done over and over again. In addition the second
way can be used to sign every driver that doesn't run natively on Windows 7.
Hay 2 formas de deshabilitar el bloqueo de drivers no firmados:
- Temporalmente (Hay que activarlo cada vez que arranca el PC) (La manera segura de hacerlo, según el readme)
- Definitivamente (siempre) (recomendada por el readme)
Forma temporal y segura:Safe Way of Disabling Driver Signature Enforcement
1) On Windows 7 bootup press F8 to get to the extended boot options screen
2) Choose "Disable Driver Signature Enforcement"
3) To start DosFlash right click on it in Windows Explorer and choose
"Run as administrator" > answer the message box with "Yes"
4) Short after the program started a "Program Compatibility Assistant" warning message
is displayed, you can simply ignore this by pressing the "Close" button
1) En el arranque de windows 7, aprieta F8 para ir a las opciones extendidas de arranque.
2) Selecciona "Disable Driver Signature Enforcement" (No se si estará traducido en la pantalla de arranque, si lo está, será algo parecido a: "Desactivar Forzado de Drivers Firmados")
3) Para arrancar DosFlash, haz click derecho sobre el ejecutable y selecciona "Ejecutar como administrador". Responde "Si" al mensaje de permitir al programa.
4) Justo despues de arrancar el programa, un mensaje de advertencia sobre "Asistente de compatibilidad del programa" (o algo asi) aparecerá. Simplemente ignoralo, apretando el boton de cerrar.
Forma definitiva (Recomendada por el readme):Recommended Way of Disabling Driver Signature Enforcement
1) Disable User Account Control (UAC)
- go to "Start Menu" > "Control Panel" > "User Accounts and Family Safety" > "User Accounts"
- click on "Change User Account Control settings"
- set the slider bar to the lowest value (Never notify) > click "OK"
2) Sign the DosFlash driver
- download the "Driver Signature Enforcement Overrider" (DSEO) from
http://www.ngohq.com/home.php?page=dseo
- start DSEO > click "Next" > "Yes" > choose "Sign a System File" > "Next" > enter the path to
the used driver (portio32.sys or portio64.sys) > "OK" > "OK"
3) Disable Driver Signature Enforcement
- start DSEO > click "Next" > "Yes" > choose "Enable Test Mode" > "Next" > "OK"
4) Restart the computer
Esta ya no me apetece traducirla

. Este metodo funciona para cualquier driver (para instalarlo definitivamente).