Why can't I sync music to my iPhone with my new iMac?

I recently purchased my iMac and I'm trying to get it to sync with my iPhone 4S, which I've had for the better part of a year now. I've authorized the computer to the iPhone so that I've now used 2 of the 5 computers I'm allowed. The iTunes software is updated with the most recent version as well.

iTunes recognizes my iPhone as it comes up in the sidebar, and I can view my info, what music is on it, apps, etc… The problem is that I've downloaded music onto this computer via iTunes Store, with my apple iD and I can't seem to click and drag the songs I want onto the iPhone. Usually I click the song I want on my iPhone, I drag it to the sidebar where my iPhone name highlights and it drops in. This time, nothing happens.

This means that you may be using a different itunes account on either of your devices, also make sure homesharing is enabled

  • Why won't my iPhone sync to my iMac? I'm trying to sync my iPhone 4 to my iMac using iTunes but every time I plug it in and click sync a pop-up window says "The iPhone could not be synced because the sync session failed to start." I made sure the cable was plugged in right and everything looked normal, in the settings, summary, etc. But it still won't sync. It's not syncing wirelessly anymore either. If anyone knows the solution to this, that would be great.
  • Who's getting the new iMac or Mac Book Pro? I don't know if I should get one! I have a Windows laptop but like I don't need a Mac I just want one because I have an iPhone and decide to have everything Apple. Give me an opinion people!
  • Transferring music from iphone to imac? I've downloaded a few songs on the "free music downloader" app on my iPhone. I can't figure out how to get this music into my itunes on my iMac so i can put it on my ipod so it is no longer taking up space on my iphone.
  • Music won't sync to iphone when i sync itunes? I plug my iphone 4 into my computer, and sync my itunes stuff. It syncs the contacts, calendars, apps, everything except my music.