Please help I am facing some problems with my iPhone. I have a Macbook Pro running on Mac OS X 10.4 and has iTunes installed on it. I used to connect the iPhone to the Macbook for synchronizing it but now the iTunes won’t recognize my iPhone when plugged in. I am not sure what is causing such issue and need your help in solving it. So if there is anybody here knows how to solve the issue, then please help. 

Re: iTunes won’t recognize my iPhone when plugged in
The problem which you are facing can be because of the connecting cord which is used to connect the iPhone to the Macbook. The connecting cord is an USB cord, which can get damaged due to improper handling or storing. A damaged connecting cord will create problems in proper communication between Macbook and the iPhone due to which the iPhone is not getting detected. Change the cord and then check if the iPhone is getting detected by the Macbook or not. 

Re: iTunes won’t recognize my iPhone when plugged in
If you think the USB cord is the reason for the iPhone to not get detected, you can use the application which helps in synchronizing the iPhone with the Macbook using the Bluetooth. Download the application and install it on the Macbook. Configure the connection settings and sync the iPhone with Macbook. If the iPhone gets synced with the Macbook, then problem is with the cord which has to be replaced or else there is some problem with the iPhone. 

Re: iTunes won’t recognize my iPhone when plugged in
Uninstall the iTunes from the Macbook and delete all the files/keychains which are related to it from the Macbook. Applications will not work properly, if any of the file associated to it is not working. Once the application is removed from the computer, download the setup for the latest version of the iTunes and then install it on the Macbook. See if you are able to sync the iPhone or not. 

Re: iTunes won’t recognize my iPhone when plugged in
Change the USB port on which you are connecting the iPhone and check if the phone is getting detected or not. The USB port of the computer may not work if the USB controller is not working properly. If the USB port is not working properly, then the device which is connected on the same port will not get detected. Hence try to connect the phone on some other port and see if the phone is getting detected or not. 

Re: iTunes won’t recognize my iPhone when plugged in
Follow theses steps and see if it helps.
Open Finder and look for the iTunes in Applications folder
Move the folder and the iTunes icon to the Trash
Open Go and type Go to Folder.
Type /System/Library/Extensions and hit return.
Find AppleMobileDevice.kext and move it to the Trash.
Similarly move AppleMobileDeviceSupport.pkg file to the trash
Restart the computer
Reinstall iTunes and see if the iPhone is detected.

Re: iTunes won’t recognize my iPhone when plugged in
Try restarting the iPhone and see if it helps. Turn off the iPhone by pressing the Sleep/wake button. Keep the button pressed till a red slider appears. Slide the finger across the slider to turn the phone off. Again press and hold the Sleep/Wake button till an Apple logo appears. Let the phone start and then connect to the computer. Hopefully it will work.