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After the completing the long-awaited Form 1116 in TT, I got an error message that I cannot understand.  It says:  "Check This Entry:  Foreign Tax Credit Comp Wks: Line 4b3c Total must be entered."  The message includes a view of a TT internal worksheet, with the missing info in a cell labelled "Adjusted basis for total passive activity assets."  I have no idea what this means, and I don't recall being asked questions about this subject while working within TT.  Can anyone tell me what I should do?