OS X :: ITunes Password Recovery - Error Message "see Attached Picture"

I recently installed a new internal hard drive on my mac which meant copying all my music back into iTunes. This has left me with a bit of work to organise all my music again, particularly those songs that I purchased through the iTunes store. The long and the short of it is that it's asking my to authorise the purchased tracks using the account that I used to buy them. This wouldn't be a problem except that I cant work out which password it is that I use on that account. The problem is every time I click the "forgot password?" button to reset it all I get is webpage with an error message (see attached picture).