The syntax error is probably due to an incorrect entry of the cell reference. More correctly when the LookupLists worksheet is active:
SolverOk [Q35], 3, vInput, [Q36], 1, "GRG Nonlinear"
If you are not sure that the LookupLists worksheet is active, use the With ... End With construct:
With Worksheets("LookupLists")
SolverOk SetCell:=.[Q35], MaxMinVal:=3, ValueOf:=vInput, ByChange:=.[Q36], Engine:=1, EngineDesc:="GRG Nonlinear"
End With
In addition, calling the function requires either the names of all parameters to be entered or none of them.
Also check that you have a reference to the Solver library https://docs.microsoft.com/en-us/off...-vba-functions
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