how reset a password of a Firewall watchguard firebox 1000?

It is not pretty, but they do have a procedure for it:

see Page 24.

http://www.watchguard.com/help/docs/FBIII+700HardwareGuide.pdf

Firebox System Area
WatchGuard ships the Firebox III with a fixed, baseline set of
functionality stored on the read-only system area of the Firebox flash disk
memory. It is possible to start the Firebox using this read-only system
area when the primary user area is misconfigured or corrupted. This
functionality allows you to:
• Troubleshoot problems where all access to the Firebox is lost
• Reset Firebox passphrases when you do not know or have forgotten
them
Fireboxes shipped before LiveSecurity System 4.1 shipped with the
original, standard functionality called the read-only system area.
Fireboxes shipped with LiveSecurity System 4.1 or later contain both the older functions and a new set of features

Read-only system area
The Firebox III has a read-only system area that the unit can be booted
into using the serial cable shipped with the Firebox. When a Firebox is
running from the read-only system area, the Sys B light and the Armed
light are both illuminated.
With the Firebox running the read-only system area, use one of two
methods to initialize the Firebox and prepare it for configuration:
• Factory default switch on back
• Out-of-band, using a modem
• Direct, using a serial cable
However, do not attempt to use the read-only system area configuration
file as a base or template for your working configuration. It will not work.
You must create a new configuration

It's not this version it't the new one 2003 with firmware Firewire 10.2. With No back switch
How flash the nvram? let me know thanks.

Sorry, I have not been able to find that information online.

There is a WatchGuard User Forum where you may find better luck finding an answer to this problem.

http://www.watchguard.com/forum/

I am assuming that you have FB III 1000; it should have a reset button at back a small pin hole which you can press with a pen ballpoint.

Here is the user guide for 7.x version:
http://www.watchguard.com/help/docs/v73UserGuide.pdf

Go through chapter 26; there are three methods to reset firebox:
1. Ethernet dongle method.
2. Using utility.
3. Using reset button.

If you have Firebox II then if I remember correctly step 1 should work.

If nothing; post back and we can dig and find out.

Thank you.

It's not this version it't the new one 2003 with firmware Firewire 10.2. With No back switch
How flash the nvram? let me know thanks.

Can you post sanitized picture(s) of your actual device so we know what product you are using and guide accordingly.

Can i flash it without system manager. Directly to the firewall. In mode console???

No you cannot; only newer XTM boxes have CLI.

It's a Firebox X1000.

If it is firebox X 1000; it would have a UP arrow key with which you can reset the unit to factory defaults.

Have a look at link below:
Reset the firebox manually, then try again:
http://customers.watchguard.com/articles/Article/1390?retURL=%2Fapex%2FknowledgeSearch%3Fc%3DAll%26p%3D2%26k%3Dfactory%2Bdefault%26t%3D%26l%3D&popup=false

Please update.

Thank you.

Good