added a vmdk to a player VM

Hello – I was trying to add a (existing) vmdk drive to my vm running under player – the vmdk was a result of a conversion, using the vm converter from a virtual pc to to player vm –

When I when to add the existing vmdk to the new VM, I got a message saying that the vmdk I was trying to add would not work in older version of player – is there a way to get around this?