This paper extends a series of experiments performed by M. Schonlau, W. DuMouchel, W. Ju, A. Karr, M. Theus and Y. Vardi [Stat. Sci. 16, No. 1, 58–74 (2001; Zbl 1059.62758)] on the detection of computer masqueraders (i.e. illegitimate users trying to impersonate legitimate ones). A compression-based classification algorithm called Normalized Compression Distance or NCD, developed by R. Cilibrasi ... [Show full abstract] and P. Vitányi [IEEE Trans. Inf. Theory 51, No. 4, 1523–1545 (2005)] is applied on the same data set. It is shown that the NCD-based approach performs as well as the methods previously tried by Schonlau et al. Future work, possible enhancements and directions of further research on this topic are presented as well.