Canon iP7250 installed on network but showing as 'offline' or 'disconnected'.

Hi.

I was attempting to set the printer up wirelessly using the USB connection via my iMac initially as the Apple Extreme and Express don't have a WPS button. My iMac had eventually found the printer as "Canon iP7250", but each time I attempted to use it, it came up on screen as either "offline" or "disconnected". Later last night, I attempted again, using my Wife's Macbook "Pro", and this time the printer was shown as "Canon iP7250 Bonjour". selecting this, the printer then operated perfectly, so I renewed my efforts with my iMac, again deleting then re-adding the printer, and this time it came up as "Canon iP7250 Bonjour", which it had not shown before. The printer then once again functioned perfectly, so I was then able to configure printing by my Ipad, my own and my Wife's iphone, all of which now function perfectly. Unfortunately the Canon 'on-screen' manual and it's 'setup' instructions are not helpful when it comes to a situation such as mine using the Apple units, and as I'm 68, self-taught on computers, and not the sharpest knife in the box when it comes to IT, this took some head scratching to sort out. Many thanks for your attempt to help me, it's much appreciated.