Check Box not working for Token module in Module administration page

Hi - i had the invite module working at one point and then I did some upgrades to modules a few days ago (I think the invite module was among them).

I've since discovered it isn't working and it said that I now need the token module. I've uploaded this but the Check Box for it in the module activation page isn't working (it is for all the other modules)

Any help as to why I can't activate this module would be gratefully received - thanks in advance