NOTE:  This is a guide showing how to replace a hard drive in a failed AV420. By doing this you void the warranty and risk damage to the unit.  If you follow these instructions you do so at your own risk and I take no responsibility for the outcome of your actions.

THIS GUIDE IS TAKEN FROM NEWMP3TECHNOLOGY.COM THE ORIGINAL AUTHOR IS COLIN SMITH. I HIGHLY RECOMMEND NEWMP3TECHNOLOGY FOR REPLACEMENT PARTS FOR ALL ARCHOS PRODUCTS.

• Take out the battery as normal
• Remove warranty sticker from battery area revealing screw (ONCE REMOVED THERE IS NO GOING BACK, - YOU VOIDED YOUR WARRANTY)

• Remove 2 screws on end of case next to compact flash card
• Remove screw on opposite end of case next to power socket
• Remove small screw from battery area
• Unclip protective corners by pushing up and in (they do not come off, just release from case)
• Unclip case from bottom black plastic strip connecting corners in the center (you can see the case is notched below the CH in ARCHOS below the screen) I used a small flat blade screwdriver pushed carefully at the notch.
• Turn over and unclip case center at opposite end (mic tv-lcd) to free center strip
• Remove case bottom and back now

• Fold screen back to reveal Torx screws holding hard drive.
• Remove Torx screws to free hard drive.

• Turn over and remove disk from connector.
• Connect the new disk and turn over, replace Torx screws.
• Rebuild case by reversing the instructions above.
• Once rebuilt with battery in place, power on and reformat disk when prompted by unit.
• Recover your files from your backup archive and you're done.

PLEASE NOTE THAT THIS DRIVE HAS ONE PLATTER, THE ONLY OTHER AVAILABLE SIZE THAT WILL FIT THIS MODEL IS A 30GB SINGLE PLATTER. MAYBE IN THE FUTURE THE SIZE WILL INCREASE BUT AT THE MOMENT THIS IS IT. THE DOUBLE PLATTER DRIVES ARE TOO BIG AND WILL NOT FIT.

IF YOU ARE THINKING OF PURCHASING THIS UNIT ONLY TO UPGRADE THE DRIVE TO SOMETHING BIGGER THEN 30GB THEN YOU MIGHT AS WELL BUY YOURSELF A NEW LCD SCREEN AND CHANGE THAT OUT WHILE YOUR AT IT, YOU WILL CRACK THE LCD WHEN YOU TRY TO PUT THE UNIT BACK TOGETHER.