There is no MAGI limit for being eligible to convert to Roth. Given participation in a workplace retirement plan, the Roth conversion would increase the MAGI for the purpose of determining whether or not a traditional IRA contribution was eligible to be deducted, but the title of this thread indicates that TurboTax said that income to support an IRA contribution was zero.
As mentioned above, deductible self-employed retirement contributions reduce the amount of compensation available to support an IRA contribution. Excluded foreign-earned income also will not support an IRA contribution.
