'16 efiling went away Oct 15, 2019
17 can be efiled now
'18 can't be efiled if the return has any of last minute retroactive extenders (passed late Dec 2019) . These have to be implemented by the IRS, and then by the software companies. Intuit has said late Feb.
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this was posted Friday....
They must have rolled out the 2018 Efile ability slowly...I tried on Friday after I saw that post, still no go for me, said I needed to update, but told me there were no updates....I'll try again today. Maybe Ive got to do that update repair tool for 2018 or something.