You didn't provide any test data with expected results, so I created my own test data.
I entered 10 records for UpdatedResponsibilityCode and numbered 1 - 10
I entered values 10 - 100 for NetCharge.
Using your formula
Code:
=Sum(IIf([UpdatedResponsibilityCode]<>1 Or [UpdatedResponsibilityCode]<>3 Or [UpdatedResponsibilityCode]<>6 Or [UpdatedResponsibilityCode]<>7,[NetCharge],0))
resulted a value of 550..... the sum of all [NetCharge] values
I changed the "OR"s to "AND"s and the result was 380:
Code:
=Sum(IIf([UpdatedResponsibilityCode]<>1 and [UpdatedResponsibilityCode]<>3 and [UpdatedResponsibilityCode]<>6 and [UpdatedResponsibilityCode]<>7,[NetCharge],0))
I try not to use negative logic, so I re-wrote the formula. I changed the original formula by changing the not equal to (<>) to equals (=) and moved the [NetCharge] value to the FALSE clause:
Code:
=Sum(IIf([UpdatedResponsibilityCode]=1 Or [UpdatedResponsibilityCode]=3 Or [UpdatedResponsibilityCode]=6 Or [UpdatedResponsibilityCode]=7, 0, [NetCharge]))
The result is 380.