1.Uninstall MaxxECU MTune from Windows control panel, add remove programs.
2.Open Windows search, type "regedit". Right click and select "Run as administrator".
3.Edit --> Find, search for the following keys: ".MaxxECU-Log" and ".MaxxECU-save".
4.Right click on both these keys and select delete to completely remove the program association.
5.Reboot computer <-- important!
6.Download and install latest MTune from our website www.maxxecu.com/mtune.
7.It should now work as expected.
Thanks to Gert Leisson for this fix.
Please upgrade to windows 10 or downgrade to Windows 7.