My twins sons and I found out the hard way today that if you plan to get an early start on the Common Application, all data inputted prior to a new version’s launch will be lost.
My sons are 2012 grads and we began their Common Apps in June, right after school let out. The 2011-2012 version launched just today and I went to access their accounts to see if supplements have been added and got nothing but error messages. After an inquiring e-mail I got this back from the Comm App folks:
“Unfortunately if you created your application before August 1, you will need to create a new application. Last season’s account information and application are no longer available. We cannot retrieve your application since all apps are removed and placed on back-up media. Back-ups can only be accessed for legal purposes at this time. For further information, please see the Privacy Policy link, located at the bottom of each page within the online Common Application.”
So if you will be entering college in 2013 don’t input any data on the 2011-2012 version. Wait until next August 1 to start. You can create an account prior to then, but anything inputted will be lost.
but thanks for the advice though 
I would also add that you make backups of everything.