what functions/formulas to use

Please help.

Column A lists all of our Group Distribution Lists in alph order and Column B lists the names of the users that belong to that group DL.
So if there are 3 people in a group DL, each person is listed in Column B as a separate line item which then also displays that Group DL on 3 separate lines.

Column D is a list of user names in alpha order appearing only once per line.
Columns E - HM Lists the Group DL's.

Columns E - HM are where I need the returned value of "x" entered in the corresponding cells when the lookup returns a value.

I.E. - So if Group: z-it-AAD-ChangeControl is in column A and Jim Dawson is in Column B, I want an "x" entered into the cell where z-it-AAD-ChangeControl and Jim Dawson intersect somewhere in columns E - HM.
I have attached a zip file w/ the excel file in it, please help me if you can.

Apply this formula in cell E2, and fill down and across. It will put an X in the intersection of a name and a group:

=IF(SUMPRODUCT(--($A$2:$A$2472=E$1),--($B$2:$B$2472=$D2))>=1,"x","")