Bluetooth Connection Unsuccessful (again...)

My MacBook Pro is right next to my iPad 4. They're seeing each other as they are included in the list of Bluetooth devices each on the other machine. I've re-started both devices, still no joy, they simply refuse to connect via Bluetooth. I've been into System Prefs on the Mac, which is where I continually click to connect to the iPad in the list of Bluetooth devices that shows up there. In Bluetooth prefs on the iPad I can also see the MacBook I want to connect to, but when I click to connect, all I get is that horrible little box saying: "Connection unsuccessful. Make sure "'acBook etc' is turned on and in range" - DUH!!!

Both machines have connected successfully in the past. The Macbook says (in Bluetooth prefs) that it's "Now discoverable as...etc."

In other words, all the usual advice that one receives when one has this problem I've already followed. Apart from throwing the pair of them against the wall, what the **** am I supposed to do about this then?

As you can see, I'm just mildly frustrated now!!