I'm being prompted to update my iPhone when I connect to my iMac.
The last time I did this I lost my entire iTunes library. What did I do wrong?
iPhone 5c, iOS 8
No idea.
You lost your iTunes library from your computer when you updated an iPhone?
I have never lost anything, nor has anyone I know.
Your iTunes library is separate from everything else on your device. The iTunes library should be on your iMac. If you update your phone, you would just sync your music library back to you phone. Either way, make sure you perform a backup of the device before you begin the update.
Sorry, I meant the last time I synced my iphone with my iMac.
"iTunes library" - do you mean the iTunes music/media on your phone?? If you synced with a computer you never synced with before, the music/media and apps on your phone will be replaced by whatever is in the iTunes library on that computer - if nothing there, everything on the phone is deleted. You were warned that would happen when you tried to sync.
To prevent this, transfer all purchases on your phone to iTunes on your computer before syncing.
I think you actually nailed the problem when you said, "To prevent this, transfer all purchases on your phone to iTunes on your computer before syncing."
It's unclear to me how to transfer everything. There doesn't seem to be an obvious way. I follow all the prompts and still get the error that there are still purchased items on my phone that might get deleted when I sync.
With phone plugged into iTunes"
iTunes menu > File > Devices > Transfer purchases
Updating My iPhone without Losing Data?
