iPad Air 2 and iMac not syncing iTunes content

[BarkingGhostar]

I noticed my wife's iPad Air 2 wasn't syncing all iTunes music. The iTunes is running on her late 2011 27" iMac running the original Lion OS X. A couple of nights ago I noticed the music was set to manually sync, which was not standard. I changed that and was warned that music on the iPad would now match with what was in iTunes on the iMac.

Okay, but it isn't doing that. I left the iPad connected directly to the iMac for a day. Nothing synced. I used the Apply and Sync options in iTunes on the iMac, and also went into the iPad and click the button. I then disconnected it and plugged it into the charger since Sync over Wifi while charging has always been enabled. Still, not syncing.

While I admit that there must be 30-40GB of music on the iMac's iTunes (all ripped from CDs), we are talking about a 128GB iPad Air 2. Anyone got any ideas on what to try?

 

[Tyranicus]

I can't guarantee this will fix your problem, but you might try upgrading the iMac from Lion to El Capitan. Lion does not support the most recent version of iTunes, so upgrading the OS and then upgrading iTunes may help.

 

[BarkingGhostar]

I can't guarantee this will fix your problem, but you might try upgrading the iMac from Lion to El Capitan. Lion does not support the most recent version of iTunes, so upgrading the OS and then upgrading iTunes may help.

I would do this if it were my personal computer. Being paranoid over data loss, I would have to labor over another external backup option and assume from the get-go that everything will go wrong, get lost, etc., etc., etc.

I even asked in the past of the dangers, pitfalls and consequences of upgrading and even did this on heavily traffic'd mac specific forums and not even they could instill any confidence and warned me. And I am not about to listen to anyone in the Apple store (complete idiots).