There are two common ways to use the SUMIF function with error handling to ignore errors in Excel:

1. Using the IFERROR function:

This method incorporates the IFERROR function within the SUMIF function itself. Here's the syntax:

```excel
=SUMIF(range, criteria, IFERROR(lookup_range,0))
```

- range: The cell range containing the data you want to sum.
- criteria: The criteria you want to match against the range.
- lookup_range: The cell range containing the values to be summed (corresponding to the matching criteria).
- IFERROR(lookup_range,0): This part checks for errors in the lookup_range. If an error occurs, it replaces it with 0 (you can replace 0 with another value if needed).

2. Using SUMIFS with SUMPRODUCT and ISNUMBER:

This method utilizes a combination of SUMIFS, SUMPRODUCT, and ISNUMBER functions. It's slightly more complex but can be useful for advanced scenarios. Here's the syntax:

```excel
=SUMPRODUCT(ISNUMBER(lookup_range)*lookup_range*(range=criteria))
```

- lookup_range: The cell range containing the values to be summed.
- range: The cell range containing the data you want to sum.
- criteria: The criteria you want to match against the range.
- ISNUMBER(lookup_range): This checks if each value in the lookup_range is a number. It returns TRUE for numbers and FALSE for errors.
- lookup_range*(range=criteria): This multiplies the corresponding values in the lookup_range by 1 only if the criteria match in the range. Values with errors will be multiplied by 0 due to the ISNUMBER check, effectively ignoring them.
- SUMPRODUCT: This function sums the resulting product of the two conditions.

Both methods achieve the same result: summing values in the lookup_range that meet the criteria in the range, while ignoring any errors encountered. Choose the method that best suits your needs and comfort level.