Alright this is not for the faint of heart, but if it works you should be able to keep everything in the end.
1.Delete all the saves except the ones you desperately want to keep
2.Delete the update and reinstall NBA 2K14
3.Go to NBA2K.com sign into your MyPlayer account and go to "MyPlayer Account Settings" Delete your account.
4.Go back into NBA 2K14 and create a new MyPlayer account.
5.Cross your fingers and reopen your old MyCareer if it still remains.
I'm to afraid to try this but I think it may actually work, but as I said this is not for the faint of heart. Good Luck to anyone if they try this, but please come back and tell me how it went in the end.

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