iTunes won’t recognise iPhone

[Bethanie21]

I am trying to back up an old iPhone 7 Plus to iTunes, but iTunes on my 2011 iMac simply won’t recognise the iPhone when the device is plugged in. iMac is running macOS High Sierra. iTunes software is up to date. Any suggestions as to what we can try to rectify the issue? Trying to back up in order to set up a new iPhone 11. Thanks in advance!

 

[kazmac]

Any ideas?

1) You may have to see if there are security updates for High Sierra and install those.

2) Do you get the window that says "Trust" this computer on your 7+.

3) Finally, do you press the 7+ home button and unlock the phone before trying to sync it with iTunes?

I have had to do these in order for my 2013 iMac on Sierra to recognize iPads.

 

[HDFan]

1. Have you tried to backup to iCloud from your iPhone?
2. Have you tried different cables? Does the cable you are using work with another Apple device?

Trying to back up in order to set up a new iPhone 11.

3. What version of IOS is your iPhone 7? There can be problems if they are different.