This error generally occurs because the Parameter Units field has not been set for the parameter and matrix shown in the error message. However, it can also be displayed when you list / report Surrogate and regular analyses which have different matrices.

Enviro Data only displays this error message for the first Parameter Units error even if there are additional one that need attention. The parameters with errors are indexed in alphabetical order. In the case above with Arsenic, there would likely be more errors to correct. If this error was for Zinc, you might not expect any more. Additionally, since some routines in Enviro Data may loop through the data more than once to produce the output required so you could see the same message again before it finishes processing.

Parameters Units are used by Enviro Data for comparison for both regulatory limits and the unit conversion feature. You can associate one reporting unit (or Parameter Units) for each combination of a parameter and matrix. Unit conversion converts any units to the matching select units set in the Parameter Units. For use with Regulatory Limits, the Parameter Units and the matrix must be the same as the units (and matrix) of the limits you are checking against.

Target units can be set in the Parameter lookup table and conversion can be set in Unit Conversion lookup table, both found on the MANAGE LOOKUPS form. You can find more information on this issue in the FAQ at What are parameter units and why do I need to set them?