I had the exacdt same problem. I did not find that secret update menu one user mentioned. But when I did Online->Check for Updates, it tells me I have the latest version.
Then, on suggestion from Intuit's phone support, I reran the installer, chose the repair/reinstall option, and did a full reinstall of TurboTax. After getting the latest updates, I was immediately able to successfully transmit the return.
I did visit Online->View installed updates, and I saw that the last update was done on 2nd April. But after doing reinstallation, it told me it installed the update from April 13th. Obviously, TurboTax did not have that latest update.
So the ISSUE is that TurboTax thought it was up to date, but actually it was not. The workaround is to reinstall TurboTax. This is a bug in TurboTax.
