Syncing an iPhone 4 with a "fresh installation" of iTunes in a new computer

Question

Hi from Madrid!
I hope my English is ok and I wish you could help me because I have a little problem. My laptop has broken and died three days ago, I had the "****" graphic chip nvidia 8600M GT, and finally it burned. It was suddenly from a day to another, I have bought a new computer with Windows 7, and I haven't dared to sync with the iTunes installed in this new laptop, because I'm afraid of losing all my information and data in my iPhone 4, when syncing with the new installed iTunes for first time. In conclusion, what I'd like to know is what I have to do not to lose all my data in the phone when syncing for the first time, to pass all the data in my phone to the computer and not vice versa or combine it with the computer, because it's very important to keep it.
PD: I think I may be able to get my old iTunes library because I rescued the hard disk, but I'd prefer to know if there is something easier because what I only want is to keep my data in the iPhone: messages, saved games, etc.
Thank you very much for your help.

Answer 1

By design, the iphone will sync itunes content with one computer at a time. Any attempt to sync such content with a second computer will result in ALL itunes content being first erased from your phone & then replaced with the content from the second computer. This is a design feature and cannot be overridden. Because you replaced your computer, your phone, sees your computer as a "new" computer. The itunes content sync is one way: computer to phone. If you have photos that were synced to your phone or music ripped on your own that were not backed up, you will first have to extract them from your phone using third party software, before you do anything else, as Apple makes no provision to do so:
http://www.wideanglesoftware.com/touchcopy/index.php
Once you've done that, do the following in the order specified:
1. Disable auto sync when an iPod/iPhone is connected under Preferences>Devices in itunes.
2. Make sure you have one contact & one event in the supported applications(Outlook, Windows Address Book) on your computer. These entries can be fake, doesn't matter, the important point is that these programs not be empty.
3. Connect your phone, iTunes running, do not sync at this point.
4. Store>Authorize this computer.
5. File>Transfer Purchases(To make sure all purchased content on your phone will be in your itunes library).
6. Right click in the device pane & select reset warnings.
7. Right click again and select backup.
8. Right click again & select restore from backup, select the backup you just made. When prompted to create another backup, decline.
9. This MUST be followed by a sync to restore your itunes content, which you select from the various tabs, You'll get a popup regarding your contacts & calendars asking to merge or replace, select merge.
You should be good to go.
But, if at all possible, move your entire iTunes library from your old computer to your new computer FIRST. Also move any data you consider important: contacts, documents, calendars, etc.
http://support.apple.com/kb/HT4527