A Global magnetic card reader and printer manufacturer had received several complaints from one of his clients (one of the major national banks) about a sudden increase in the malfunction of magnetic card readers used in dozens of bank branches. The client requested an analysis that would help identify the factor(s) that could cause the malfunction. Analysis by Optical Microscopy (PLM/RLM), Fourier Transform Infrared Spectrometry (FTIR), and Scanning Electron Microscopy/Energy-dispersive X-ray revealed and identified the contamination. FTIR and SEM/EDX studies of the contamination showed a match to the organic components that can be related to skin and skin care products. As it turned out employees of all the affected branches were using the same type of the hand sanitizer that caused the malfunction.