Sum of sumifs higher than Sum???

Seems to be a simple problem, altough I seem the be overlooking the cause of the problem.
I have one column with values (F). If I calculate the Sum the value 731.182,93 shows.
All Values have a number, being part of a subcategorie (10-99) and a maincategorie (1-9). If I do a sum if for the 9 maincategorie over the same column F and use sum, the result is 763.777,24. Which cant be true, the summation should result in the same value. Somehow, somewhere somethings seems to be calculated double in the sum.ifs. What is going wrong?