iTunes error: Could not allocate a resource

I'm getting the error "Could not allocate a resource" in iTunes whenever I connect a device. I've seen this as a possible fix:

sudo rm -rf /var/db/lockdown/

I've tried that and restarted my machine a handful of times, but no luck. I've also tried the following:

• Changing USB ports.


• Delete and reinstall iTunes.


• Reset PRAM and SMC.


• Recovery mode with software update (iTunes detected the device in recovery mode).

In addition to the error, whenever I connect a device it asks me "Trust This Computer?"

This is occurring on an iPhone 5 and iPhone 6+ with lightning, as well as an iPad 3 with the old style connector.