When a tax return can't be e-filed no matter what you do
Although millions of tax returns are successfully e-filed every year, some returns simply cannot be e-filed or keep getting rejected even though there's really nothing wrong with them.
For starters, you cannot e-file returns that contain overrides, have no taxable income, where the W-2 box 1 is blank or box 16 exceeds box 1, contain IRS forms not on the accepted Forms and Schedules list, and many nonresident and part-year state returns.
For these types of situations, there's really nothing you can do to "fix" your return so you can e-file it. For this year at least, you'll need to file a paper return instead.