Try this One Hope it will work TSQL
--Syncronize tbl_users2 with tbl_users
insert into tbl_users2 (UserName,Email)
select UserName,Email from tbl_users except
select UserName,Email from tbl_users2
insert into tlb_users (UserName,Email)
select UserName,Email from tbl_users2 except
select UserName,Email from tbl_users
--this commands returns all the rows which exist in tbl_users but do not exists
--in tbl_users2
select UserName,Email from tbl_users except
select UserName,Email from tbl_users2
select UserName,Email from tbl_users2 except
select UserName,Email from tbl_users