Various systems have been developed to support and motivate volunteer activities for people with disabilities. "Minna de DAISY" is a microvolunteering system, powered by an open-source social networking system and web application, of character corrections. This system demonstrated that digital books could be efficiently produced for the visually impaired through the manual correction of errors using volunteers. According to participant interviews, those who were aware of their social contribution had a higher motivation to do social work. The feeling of community involvement promoted continuous participation. However, these studies do not precisely discuss the contribution of communication between system managers and participants. Some literature reported that interactions in a social network improved participant awareness of the purpose of their work. In this study, we aim to demonstrate the effect of communication on participant motivation and likelihood to continue microvolunteering.