Though a relatively new phenomenon in Spain, online university education has already managed to gain public acknowledgment. The International University of La Rioja (UNIR) is one of the few high educational institutions in this country to provide the opportunity of high quality distance learning. Having a chance to work with students who are doing a Preschool Education Bachelor's Degree at UNIR, we have become particularly interested in those opportunities that online education gives us to examine students' written production skills. In spite of the fact that most of our students have been studying English for a number of years, their level of written production is still low. What's more, they tend to make rather repetitive kind of mistakes, most of them related to the transfer phenomenon in L2 acquisition. The present study is aimed at identifying and analyzing one of type of error made by Spanish-speaking students: the use of adverbs of frequency and their position in the sentence. To do this, we have analyzed the language corpus compiled out of 399 contributions written by 92 students to the virtual forum designed as part of the subject ICT tools applied to the learning of English language.