I have the exact same issue. Actually governing numbers for 2018 calculated and considered correct by several previous Turbo Tax versions. I admit that I am a bit suspicious of the suggested workaround and would hope someone at Turbo Tax might be reviewing this issue (and it might just be a software bug).
Form 1116 - Foreign Tax Credit Comp Wks: Incoming C/O Utilized should not reduce the foreign taxes below 0.
However, the suggested solutions seems unreasonable. I guess it's the minimal way of fixing a Turbo Tax bug by changing the tax return without changing the information relevant for the present, but the resulting Schedule B for from 1116 seems correct when Turbo Tax throws out the error and doing the suggested adjustments modifies the Schedule B to give the same overall current tax credit carryover but no longer the correct historical distribution in accordance with previous filings.
I talked to both tax experts for the desktop version and online tax experts and none of them seem to understand what is going on. My best guess would be a system bug that came with the update. in my case the error is even governing the year 2018, which was calculated and considered correct by several previous Turbo Tax versions.
