TurboTax retains online tax returns for the past seven years, the same retention time as the IRS for federal tax returns.

A tax year 2011 online return will not be available.

about the only items that would be available are any w-2s you had for that year. you get copies from the Social Security Adm

https://faq.ssa.gov/en-us/Topic/article/KA-02501