There is a chance that the downloaded McAfee software has corrupt components. I suggest uninstalling it. Follow the procedure below:
1. Click Start (the Windows logo button), then click on Control Panel on the right hand side of the menu.
2. Double-click Programs and Features.
3. Select the McAfee SecurityCenter product.
4. Click Uninstall and follow the steps provided.
5. After the removal process is finished, restart your computer.
To reinstall McAfee, click the link below to get the steps:
How do I install McAfee Antivirus Plus for MSN?
http://answers.msn.com/solution.aspx?solutionid=98a6edf8-c45d-49ef-8cad-bca7f224759e
If the same issue persists, get in touch with MSN Support via phone so that you can be directly transferred to our dedicated McAfee Support Group. Please check my private message for their contact details.