I have the same problem, unable to import from Merrill Edge. The same error message. Contacted ML , I was told it is TT. Called turbotax was told it is ML. Spent hours on the phone, sharing screen with TT's multiple representative. They suggested to enter 1099 manually, some even tried, to do it with me , just to realize, it is too big job, to enter it manually, and accidentally dropping off connection. My 1099 b has thousands of entries, 140 pages.
Some articles on internet pointed to TT limitation of import to 10,000 transaction , 4MB. I cannot find, if my 1099 is affected by this limitation.
Others suggested turning of firewall. Turned off fire wall, tried to import, no luck, the same problem.
I also wiped out my computer to factory setting , reinstal and updated TT, antivirus and trried again to import, the same error.
