Occasionally on Windows XP iTunes will not communicate with Outlook 2007 even , despite previous, successful sync attempts. It appears this issue can be caused by the presence of other Outlook plug-ins. Rather than removing these which you might need as is the case for me or being unable to remove them due to a policy applied to the computer use the following workaround:
- Close Outlook 2007 and iTunes.
- Unplug your iPhone and wait about 10 seconds.
- Plug the iPhone back in.
- If iTunes does not auto-launch then launch it.
- Go to the Info tab check that it looks like the above picture and press the Sync button. Allow the Sync to finish.
- Confirm that any new Outlook 2007 events are present on the iPhone. If they are you can re-launch Outlook and begin using it again. Otherwise restart Windows and attempt this process again.
If this fails see this Knowledge Base article, especially if the Info tab will no longer allow you to select Outlook as a syncing option.
If all the above fails, remember that you can launch iTunes alone and sync. iTunes does not require Outlook to be running to sync.