Hi Saket, Thank you for reporting this issue. arrayQuality is an old package, and it looks like there is some compatibility issues between the code and the current version of the R functions used by the package. I will try to fix the problem, but it may take some time, as this would be done only during my free time. In the meantime, you can try the other options available to analyze microarray quality , such as the arrayQualityMetrics package. Best, Agnes