I have an iMac (21.5 inch, Mid 2011). It has 4 USB2 sockets on the back. I want to expand by using a 10 port USB Data Hub. I have tried to use an Anker 10 port USB3.0 hub but it doesn't seem to work. Is this because the device is faulty or do US

Any external hub will need to be powered because no USB 2.0 port has enough power for even a few USB devices especially if they are power hungry.

You never mentioned what it was you hung off this hub. If they are hard drives there is definitely a limit. Anker should be able to tell you what that is.

It is possible to hang USB 3.0 off your Thunderbolt port using a Canex adapter. They are not cheap but work. I have one. Don't know if they are still available for your model, maybe in the sale bin, because Apple has twice changed the Thunderbolt port since then to make life "more interesting" for its users.

For a company that still uses Indesign CS2 for its publications, it is very free with forced (unnecessary) updates and incompatibilities for its users.

Peter

iMacs need a powered USB hub to work. I'd recommend contacting OWC (www.macsales.com) as they specialize in Macs and can help you select a USB hub that will fit your needs.