When I start my iriver H10, it is stuck on initializing

If you leave it long enough it should initialise. I had to plug it into mains power so the battery doesn't go flat while it's trying to ido so. But then again, your battery might last longer than mine as mine was a factory repair, so there's a laundry list of issues I've had with it.

Try Here:

http://iriverinc.com/support/hd/

If that doesn't work check out the forum at:
http://www.misticriver.net/forums/h-10-h-20-series/

same problem with mine...i tried to use rockbock firmware...it works but you have to be patient...you have to reset it time and time again before it works....it still works anyways rather than the iriver firmware...

This is straight out of p. 67 of the user's manaul, available on iRiver website (it may not work if the computer does not recognize the device):

Initializing H10
67
Additional information
Firmware upgrade
66
What is firmware ?
It is the operating system that works in the H10.
iriver provides you with the latest and best features through Firmware upgrade.
You can choose manual or automatic upgrade function.
For information on automatic upgrade, refer to the iriver plus instruction manual.
Manual firmware upgrade
1 Select [Option - Firmware Upgrade] from the menu in iriver plus.
Do not disconnect H10 during firmware upgrade.
Internet must be connected for the "Firmware Update" function.
Change to "Player must be connected to the PC for Firmware Upgrade function.
Note
Please initialize H10 player in the following cases.
All music, pictures, text, and data will be erased from the player during this initialization.
- if there appears to be corruption on the internal hard drive.
- if an error message displays and the player doesn't boot properly.
1 Connect the player and PC using the cable supplied with the player.
Open iriver plus.
Select [Option-Portable Device Initialization]. 2
3 Click [Start] to begin initializing.
Initializing H10
A
A
B
B

This is straight out of p. 67 of the user's manaul, available on iRiver website (it may not work if the computer does not recognize the device):

Initializing H10
67
Additional information
Firmware upgrade
66
What is firmware ?
It is the operating system that works in the H10.
iriver provides you with the latest and best features through Firmware upgrade.
You can choose manual or automatic upgrade function.
For information on automatic upgrade, refer to the iriver plus instruction manual.
Manual firmware upgrade
1 Select [Option - Firmware Upgrade] from the menu in iriver plus.
Do not disconnect H10 during firmware upgrade.
Internet must be connected for the "Firmware Update" function.
Change to "Player must be connected to the PC for Firmware Upgrade function.
Note
Please initialize H10 player in the following cases.
All music, pictures, text, and data will be erased from the player during this initialization.
- if there appears to be corruption on the internal hard drive.
- if an error message displays and the player doesn't boot properly.
1 Connect the player and PC using the cable supplied with the player.
Open iriver plus.
Select [Option-Portable Device Initialization]. 2
3 Click [Start] to begin initializing.
Initializing H10

I would be willing to bet your hd has crashed, you could try to fix it check ebay for one that works
'

I have done this. my iriver is almost full i have the 20gb, when the you do the database refresh, it just takes a really long time. mine takes about 2 hours to finish, once you see the clock on database refresh you cant do anything but wait till its finished.

Please go to my blog to fix your problem. http://terminaltech.blogspot.com/2007/04/iriver-h10-freezing-at-initializing.html

Reacquire firmware from IRiver website

it is not recommended to initialize while synchronising this will fry a couple of circuits inside