I have recently been having trouble downloading updates. I opened Sparrow and it said that an update was available, as usual I went to the Mac App Store and went to the updates tab. However it said that No Updates Were Availiable. I then clicked on the Purchases tab and Update was there on the button next to sparrow. When I click the update button an error message comes up saying "You have updates available for other accounts. To update this application, sign into the account you used to purchase it." I am logged in to the app store using my only Apple ID (used to purchase Sparrow and the other Apps) and have tried logging out and back in again but nothing has changed. If anyone can help me that would be great! Thanks in advance.