I had the exact same problem with e-file rejected related to Vanguard International funds. I tried all the steps above after 4 rejections, the change that appears to have corrected the problem was changing the word "various" under the date dividends were paid" on Form 1116 to a specific date. Vanguard doesn't report the date paid so I just entered 12/31/2020 and the e-file was finally accepted on the 5th attempt. I sure hope TurboTax can get this fixed!! I spent several hrs trying to identify the problem and make the changes.
