Hi Serge,
Looks like something is conflicting with McAfee/ Windows, so please clarify/try the following:
• How long you are using McAfee on this computer? If you are using it for the first time did you use any other security programs in your computer before?
• If Yes, was that removed completely, what is the name of that program?
• Click on
Start> Click on
Run> Type
MSConfig> Click on
Ok> Click on
Startup Tab> Click on
Disable all on the right bottom> Click on
Services Tab> Make a check mark on
Hide all Microsoft Services on the left bottom> Disable all the unwanted services that you find over there and reboot the computer
• Also try to scan the computer for infection by using this Anti-Malware tool
http://www.malwarebytes.org/mbam.php. Click on Download, Install it and scan the computer