Although software development projects increasingly incorporate virtual team members they still fall prey to risks which produce challenges as do co-located projects. Most research performed on project risk was conducted on projects using traditional co-located team members. This paper reports on the results of a survey of over 150 Information Technology (IT) practitioners. One goal of the survey was to identify differences in the degree of impact between risk factors on virtual software projects and those on co-located software projects. Out of fifty-five surveyed risk factors, seven risk factors showed significant differences in impact on the successful completion of projects in these two types of project environments. Additionally, the results showed a greater impact for each of the seven risk factors on virtual rather than co-located software projects. These results can be useful to practitioners who are managing in a virtual environment and need to correctly identify potential risks.