Experimental data about high-energy particle fluxes obtained in 1990-2000 in the Riabina-2 experiment on board MIR orbital station are analyzed in the sense of data failures. There are two types of failure. The first type is represented as sharp positive or negative spikes on the relatively smooth time profiles of the particle fluxes. The second type is randomly distributed data gaps with durations of up to tens minutes. These two kinds of the data failures are formalized in the form of "failure occurrence probability" (FOP). The comparison analysis of the FOP with solar activity, solar wind conditions and geomagnetic activity shows that one half of the observed data failures are owing to noise originating mostly from electronic equipment on board MIR station. The other half of the data failures are closely connected to geomagnetic storms and interplanetary disturbances. The space station surface charge and radio signal distortion in disturbed ionosphere are considered as possible phenomena responsible for the data failures.