Unable to install Rock-ons

Whats up everyone,

I’m new to Rockstor ( and Linux systems in general )

I seem to be unable to check for and download new Rock-ons. All i get on clicking the update button is -
"
Houston, we’ve had a problem.

Unknown internal error doing a POST to /api/rockons/update
"

And No error message or anything after that.Any idea what this is?

Cheers