Machine-generated data is divided into its metadata (or contextual data) that is indicative of a data container, and the data values themselves that are indicative of sensed variables. The metadata is checked to obtain a container integrity indicator of whether the data is accurate based on characteristics of the data container. The actual data values are subjected to quality checking to determine whether they have been corrupted by inaccuracies. Data corresponding to inaccurate metadata or inaccurate data values themselves is quarantined, and correction logic attempts to correct any inaccurate data. Corrected data is output with the verified data.