How to sync iPhone library with iPhone with deleting phone's content?

My computer's registry became corrupted so I had to reinstall Windows. I'm running the latest version. I have the latest version of iTunes too.

When I go to sync my iPhone to my computer, it won't let me automatically update new music downloads or playlist changes from my computer to my iPhone.

iTunes says,
"Are you sure you want to remove existing music, movies, TV shows, books, and tones from this iPhone and sync with this iTunes library?"
"Music, movies, TV shows, books, and tones synced to your iPhone from other iTunes libraries will be removed and items will be synced from this iTunes library."

My computer is authorized for this iPhone.

Is this just a standard warning or will I love all the save data on my iPhone for my apps? Just making sure.

IPhone camera freeze/ fail to open?

I just got the iPhone 5c maybe a month ago, I haven't dropped it or gotten water or anything near or on it. The camera works most of the time but once in awhile it will freeze up and fail to open. Any apps that use the camera will also freeze and won't work. What could be the reason why my camera does this?

Why does my IPhone battery drain when in my car?

My phone could be at 100% and within 10 minutes it'll be down to 1% when I'm in my car. Why is this?

Windows 8.1 won't update stuck at 60%?

I have a Windows 8 computer that I rarely use. I basically live off of my iPad and iPhone. When it came time to sync my phone and my iPad I noticed that I had an update. Windows 8 update to Windows 8.1 but it won't let me update I've tried several times and nothing my computer always get stuck at 60% or it says it was unable to update. Please help, negative comments will be flagged thank you.

Why isn't my Wi-Fi working anymore on my Iphone 4S?

It just suddenly stopped working. I mean, only if I have the phone 2 feet or less from the router, only then it will connect to Wi-Fi. If I'm more than 2 feet away, it won't find the router. It's not just on my router at home. It's happening with my mom's router too and I'm in a different state. Anyone know what the issue is?

I lost my iphone 4s on a train?

I left my iphone 4s on a train yesterday evening. I checked on icloud to find it but the device is offline and i tried calling but it went straight to voicemail. Advice would be wonderful. It was the train from southstation to norwood on the franklin line. Should I try calling the station?

Atheists Jesus went into the desert by himself for 40 days how did Satan find him?

If you went into the desert for 40 days, nobody can find you. Remember this was before they used cell phones that is made from the deadliest war since WWII. Over 5 million people have been killed in the Democratic Republic of Congo to mine for minerals for make ipads, iphones.

Why are there songs stuck on my new iphone 5?

So i just got a new phone for christmas. I have it all set up and connected to itunes. I have songs that i can't get off my phone, all the songs have the icloud sign next to it. But when i plug it into my itunes and check what is on the phone it says there are no songs on it.help! Some of the songs on my phone arent even in my library.

How to get my iphone 5 charger to work?

I plug my charger in an it vibrates saying it's chagrin then it stops then vibrates etc. Now it's not working at all. What do I do? I only have 16%

Why does my Wi-Fi keep going out?

I have a Netgear as my Wi-Fi and i have a window 7 toshiba computer i think the problem is coming from the laptop because my iphones and andriods and everything else tht uses Wi-Fi works. But my laptop works for a certain length of time and the Wi-Fi will just cut off in the middle of doing something, it first has a yellow trigangle and it said no network found. Is there any suggestions on fixing this or anyone know how to fix it. Oh and also when i press it sometimes says limited access.