I get an error of "few arguments". And I did name the range of sheet2 as
GUTable, I don't understand why you put the B$2 in the match function and $A2
in the countif function. What are those suppose to represent?

"Harlan Grove" wrote:

jac007 wrote...
....
. . . Sheet1 contains unique group names in B1:Z1 and unique user names
in A2:A256. Sheet1 is used to put an "X" in each cell where there is a user
that has access to a group(ex. B4 has an "X" because that user has access to
that group). . . .

OK, groups along the top row and users down the left side, and you want
X's in the cells framed by the group and user IDs.

. . . In Sheet2, I have the group names going down Column A, and I
have the users going down Column B through E. Just as listed below.
....
My questions is, how do I put an "X" in a cell in sheet1 where that user and
that group matches to the user and group from sheet2? Vlookup didn't work so
does anyone know of a function that can do this. Thanks!

INDEX/MATCH would be more useful, along with COUNTIF.

If the table of groups and users in Sheet2 were named GUTable, you
could try the following formula in Sheet1 cell B2.

Sheet1!B2:
=REPT("X",COUNTIF(INDEX(GUTable,MATCH(B$2,INDEX(GU Table,0,1),0),$A2))