I found a Henry A Wicoff, age 8 in Wade Township, Jasper County, Illinois on the 1880 census.He was listed as a nephew, living in household of Parkman Beals, and Pricilla
Then found marriage record for Parkman Beals to Percilla Wicoff, Jan 15, 1865.So he would be a son of one of Priscilla's brothers.
Nearby in 1870 was James ?Wycoff, 47, b. KY.In 1880, near the Beals household, was a Julia Wicoff, with family of children, who had a Kentucky born father.
Going back to 1860, in Jasper County, lived the following household.
Wycoff, James L, 37, farmer, KY
Julianna, 35, KY
Thomas H, 16, IN
Priscilla, 14, IN
Sylvester, 12, IN
Theodore, 10, IN
Wm Marshall, 6, IL
Milburn, 2, IL
In 1880 Thomas H was living with his mother and several siblings, including Milburn, and several born after 1860.Also in the household were a Wicoff granddaughter, Ida, age 13, and a Wicoff grandson, age 7.Checking the 1870 census shows the daughter to have been Thomas' daughter.He had a wife named Sarah, b. abt 1846 in Indiana.
Also on the 1880 census Henry A Wicoff indicates his father to have been born in Indiana.So my guess he was a son of Thomas Wycoff and Sarah, living with his aunt and uncle.
Illinois marriage records show Thomas H Wicoff married Sarah J Hartman, July 17, 1864 in Jasper County.Followed by Thomas H Wicoff marrying Margaret E Smith, April 22, 1881 in Clark County.
Not positive this is your Henry A Wicoff, but the most frequent spelling was Wicoff, and other things seem to fit.And this was the only Henry Wycoff, with any spelling of the last name born in that time period that shows up on the 1880 census.
1910 census shows a Henry A Wicoff, b. abt 1874 in Illinois,but indicates Illinois born parents.However if he didn't live with his parents as a child, he may have just known they were from Illinois.By 1920 this Henry A Wicoff was living in Decatur, Illinois in Macon county. By 1930 he was living in Danville, Vermillion County, Illinois.His wife's name was Alma.And in 1930 he still had his father as born in Illinois, but switched his mother's birthplace to Indiana.
Hope this helps.