Troubleshooting If the custom data lookup definition rules are not behaving as expected, check for certain conditions. If the custom data lookup definition rules are not behaving as expected, check for the following conditions: Ensure that the matcher variable is not read-only. Since users cannot change read-only variables, there cannot be an on form change event for read-only variables. Ensure that the data in the matcher table is correct. If the lookup requires an exact match, verify that there is a matcher table row for each possible combination (including blank values). The lookup fails if cannot find a matching value. If the variable is an option or check box, it always has a value, so you must select Always replace. Verify that you have not created a recursive rule, such as:If Variable A = 1, then Variable B =2. If Variable B = 2, then Variable A = 2.