I have a 4th gen 20G iPod that stopped working. I could hear the iPod start up, and then stop, then start, then stop, and it would display a folder icon with an exclamation point. Heard thats a hard drive failure, so I ordered a new hard drive and installed it. It still displays the folder icon with the exclamation point, but it will now sync to my computer and it allowed me to add music to it. But as soon as I disconnect it, the folder icon appears again?

Which version of ipod 3rd 4th or fith gen >??????
iPod Classic password
This works on an iPod 5 th gen
Click start control panel scroll to folder options tick in the box to show hidden files and holders

connect your Ipod to your computer
Click start click click on you Ipod to open then go Ipod controls device there should be a folder saying locked

Right click select rename to open or delete the folder your Ipod should now be open.
If you need more help with this post a reply.

You need to solder one in
Replace 4th Generation iPod Battery http://www.youtube.com/watch?v=v8-KUt8PVFY iPod Touch 4th Gen Instructions http://www.youtube.com/watch?v=X1B5iu3ILkY How to replace your ipod touch 4th gen Battery

you might have to reset it to factory settings

The 4th generation iPod is a portable media device that can play music, videos, and display photos.

Occasionally, you may run into issues with the iPod where the player has trouble working.

Restoring your iPod to its factory settings will often correct any software issues the player may have by wiping all of the data off of the iPod, and restoring its software to its original condition.

Restoring your 4th generation iPod can be done in just a few minutes, and requires the help of your computer.

Connect your iPod to your computer using the included USB cable, just as if you were going to sync it to add music or other data.

Launch iTunes if it does not launch automatically, and select your 4th generation iPod from the list of devices on the left side of the screen.

This will launch information about your iPod in the main iTunes window.

Click the "Restore" button in the middle of the iTunes window to begin restoring your 4th generation iPod to its factory settings.

Your computer may ask you to enter an administrative username and password to continue. A progress bar will then appear letting you know the status of the restore.

Wait for the progress bar on the screen to finish and then disconnect your 4th generation iPod.

The iPod is now restored to its factory settings.

You can reattach the iPod to your computer and set it up again, just as you did the first time you used it.

hope this helps

also you could try This works on iPod 5th gen
click start control panel scroll to folder options tick in the box to show hidden files and holders

connect your Ipod to your computer


click start click click on you Ipod to open

then go Ipod controls device there should be a folder saying locked

right click select rename to open or delete the folder your Ipod should now be open

Here are it's features

Product Features

• Portable speaker/display system designed for all "dockable" iPods**
• Crystal-clear, 7-inch widescreen LCD display with 480 x 234 resolution
• Pair of aluminum cone neodymium drivers and Class D digital amp
• Built-in iPod docking station; 3.5 mm auxiliary input for other devices
• Measures 8.7 x 1.7 x 6.5 inches (W x H x D); 1-year warranty

Notice
Notice it say ALL iPods, as long as its not the 5th gen ipod with the new dock connector it should work fine.

Ipod is not ABLE TO FIND THE OS ON YOUR HDD.
try to bring it close to your ear an try to hear. See if you can listen to clicking sound. if it does click, your in trouble as your hdd is messed up..
nothing much you can do about it, just when its trying to start and it starts clicking bang your ipod ( on ur palm ) as this would help the hdd needle to skip and bad sectors and might work again !
good luck.

try reseting it

JVC KS-PD100 iPod Interface Adapter (257KSPD100, sold separately). This optional iPod Interface Adapter supports audio playback for the following iPod models - iPod click-wheel (3rd gen), iPod photo (4th gen), iPod mini (1st/2nd gen), iPod nano (1st/2nd/3rd/4th gen), iPod video (5th gen), and iPod classic (80/120/160GB). The KS-PD100 is not compatible with the iPod touch (1st/2nd/3rd gen), iPod nano (5th gen), or iPhone (2G/3G/3GS). This iPod interface will also not charge the iPod nano (4th generation). *Apple firmware updates may change functionality results.

There u go.....

I'm sorry, but the bottom line is that you cannot watch videos on the V55 with a 5th gen iPod. 4th gens work fine though. Apple made this change in their iPods after several aftermarket companies began losing money in their products not selling. In response, iPod apparently teamed up with those companies and installed a chip to "decode" the video content. You can hear audio, but see no video. It stinks, I know. I am just glad that I have a 4th gen video iPod.

However, I am posting here because I am looking through posts and blogs to find out how to fix my V55 as the screen is intermitently going bad.

You'll need to replace the click wheel. You can get one on ebay for about $10 and put it in yourself or let a repair shop do it for you for about $40.

This is a common problem on ipods.

Sounds like a possible hard drive failure. Have you tried to do a reset? Toggle the hold button on and then off. Then hold down the menu button and the center button at the same time. hold them until the screen flashes. then release. You may have to try this several times.