have recently downloaded the Video file and then added that file to the iTunes. I will able to play that file on the iTunes, but if I try to use that converted mp4 file to the iPhone, I don’t able to play that. I get the error message as below:
Quote:
movies cannot be transferred because iphone does not support that video format..
What is the wrong with mp4 file. Why did that mp4 file is not working on iPhone? If you are having any solution for this, then give me that. 

Re: iPhone Won’t Play Video Files (mp4)
Follow the steps below:
You have to first import the Videos by clicking on the File and then Add to Library.
Now select the Video which you have imported from the Movies tab.
Now select the Advanced and then Create iPod/iPhone Version.
Done.

Re: iPhone Won’t Play Video Files (mp4)
You have to use the Avex DVD to iPhone Video Suite which is having features as below:
Convert DVD, Tivo, MPEG, WMV, AVI, DivX/Xvid, RM, MOV videos, etc to iPhone MP4 video.
Built-in X!-Speed transcode technology. Up to 3x faster than conventional converter.
Fully optimized for Dual-Core, HyperThread Processors, SSE2/SSE/MMX/3DNow
Support H.264 and MPEG4 video in MP4 format used in Apple iPhone.
Adjustable video size for playback on iPhone and on TV screen as well.
Optimized settings for superb video playback on Video iPhone.
Support conversion in batch mode.

Re: iPhone Won’t Play Video Files (mp4)
You can use any of the application below, convert the file and get solved for your problem:
Videora iPhone Converter
Xilisoft iPhone Video Converter
iPod/iPhone Version
iPhone Video Converter

Re: iPhone Won’t Play Video Files (mp4)
iPhone will support for the following Video files format. So, just convert in any of that format and solve your problem:
H.264,
MPEG-4 in .mp4,
.mov,
.m4v formats and MP3,
protected AAC,
AAC,
Audible,
Apple lossless in .aac,
.mp3,
.m4a files.

Iphone won’t play video files (mp4)
I have apple iphone which is 3 months old. Last day I got first season of “mad men” and I convert it to mp4 and added it to itunes. I able to play that video using itunes, but whenever I tried to send that video to iphone it said that “iphone does not support that video format”. I don’t know why Iphone won’t play video files (mp4). Please help me to fix this problem. 

Re: Iphone won’t play video files (mp4)
The video has to be converted into the iPod/iPhone Version. You can do this in the following ways.
1.First import the video into the iTunes. You can do this in the following ways.
File -> Add to Library
2.Select the video that you import. 
3.Now click on the Advanced -> now select iPod/iPhone Version. 

Re: Iphone won’t play video files (mp4)
Use following steps to send video to iphone.
Step 1: Make sure you have updated your QuickTime software to version 7.0.3 or later. If you don’t have QuickTime 7.0.3 installed, get it now.

Step 2:Open QuickTime 7 Pro. If you don’t have it, get QuickTime 7 Pro today.

Step 3:Choose “Open File…” from the File menu.

Step 4:Choose “Export…” from the File menu. 

Step 5:Choose “Movie to iPod (320×240)” from the export drop down list and click the Save button.

Step 6:To get the movie onto your iPod, launch iTunes 6 (or later). If you do not have it, download iTunes now.

Step 7: Drag your new movie file into your iTunes library in the folder or playlist of your choosing.

Step 8:Attach your iPod to your computer and synch the iPod with iTunes. For detailed synching instructions, see the iPod tutorial. To play the movie on your iPod, select “Videos” then “Movies” from the iPod Main Menu. Movies will be listed here alphabetically. Click on the desired movie to play. 

Re: Iphone won’t play video files (mp4)
Try to restart your iphone. You can do this in the following ways.
To restart iPhone, first turn iPhone off by pressing and holding the Sleep/Wake button until a red slider appears. Slide your finger across the slider and iPhone will turn off after a few moments. Next, turn iPhone on by pressing and holding the Sleep/Wake button until the Apple logo appears. 

Re: Iphone won’t play video files (mp4)
First try to verify that your device is syncing and playing movies that have been properly converted, follow these steps:

1. Download this iPod-compatible sample movie: sample_iPod.m4v (right-click or Control-click the link and save it to your desktop). You may need to unzip this file if it is not automatically handled by your web browser. On Windows XP, right-click the downloaded zip archive and choose Extract All.
2. Open iTunes and add the sample movie “sample_iPod.m4v” to your Library from the File menu. Note: The file may also appear assimply “sample_iPod”.
3. Connect your device and sync the pre-encoded sample movie to it.
4. Eject your device in iTunes and verify that the “sample_iPod” movie plays correctly.