V 1.4 hanging on admin log in

[wilfred11]

Hi guys, I have just installed v1.4 on a new client. Installation went fine but when I go to the admin section I get the browser hanging, two "loading" signs come up and the dashboard does not appear.. see enclosed screen capture.
The installation went well but as the database had been used for an installation of V3 I had it wiped (we hadnt done anything on it) so it would be clean for this install. PS did notice that a database was present so I had to change the prefix (not sure if that is relevant) but other than that all went ok.

Anyone got any clues? : Best wishes : Dom