I just upgraded my iPhone to the 6 from 4S.  I have Outlook 2007, which worked just fine with my 4S to sync through iTunes.

Now, for no reason, I am getting a sync error.  After 2 1/2 hours on the phone with iTunes....deletes/installs, etc. it is concluded it is not a iTunes problem.  I can not find any where on how to fix this sync error.  Any suggestions?

Hi,

For better assisting you on this matter, could you help me with information below:

1.  What was the sync error was?
2. Is your software up to date, both Windows/Office/iOS?
3. What is your Outlook account type? IMAP, Exchange or POP3?
4. Are you using Cache mode or Online mode for you Outlook? When using an OST file, only information stored locally, or cached on your computer, will be available to sync.

Meanwhile, we can try to reset Sync history to see if the issue can be solved:

1. Back up your data, refer to this article for Backup details
2. Open iTunes.
3. From the Edit menu, choose Preferences.
4. Click the Devices tab.
5. Click the Reset Sync History button.

If the issue continues and you know all of the data is on the computer:

• Reset the Sync History again using the steps above.
• Select the device in iTunes and click the Info tab.
• Scroll down to the Advanced section, and under "Replace information on this iPhone/iPad/iPod touch" select Contacts or Calendars.
• Click Apply.

If the issue continues and you know all the data is on the iPhone, iPad, or iPod touch:

• Reset the Sync History again using the steps above.
• Remove all of the contact and calendar information from Outlook.
• Select the device in iTunes and click the Info tab.
• Scroll down to the Advanced section, and under "Replace information on this iPhone/iPad/iPod touch" make sure Contacts and Calendars are not selected.
• Click Apply.

Reference used: Troubleshooting Sync Issue