Play Video File On Android Device But Getting Error - Cannot Play Video

Im using Eclipse created new android project.First thing i added to the menifest xml file two lines:

Code:
uses-permissionandroid:name="android.permission.INTERNET"></uses-permission>
<uses-permissionandroid:name="android.permission.STORAGE"></uses-permission>

And this is the complete menifest file code:

Code:
xmlversion="1.0"encoding="utf-8"?>
manifestxmlns:android="http://schemas.android.com/apk/res/android"
package="com.AllFormatsVideoPlay"
android:versionCode="1"
android:versionName="1.0">
[code]....

Now i tried to play a video file .3gp from the internet youtube link via my android device ! not emulator. And it worked! But when i tried to play a video file .3gp or .mp4( i converted the mp4 from 3gp ) its not working. Im getting error "Cannot play video Sorry, this video cannot be played"

Tried to play with the link to my device wich is: I:DCIM100MEDIAVIDEO0030.3gp or .mp4 or tried this: I:/DCIM/100MEDIA/VIDEO0030.3gp with "" like: "I:/DCIM/100MEDIA/VIDEO0030.3gp ";

I tried to remove the I: but it didn't change anything.This is the main code im using to play the video files on my device. And there some lines i marked with // wich i used to play from the internet and im not using now.

Code:
com.AllFormatsVideoPlay;
import
android.app.Activity;
import
android.graphics.PixelFormat;
import
[code]....