Many thanks to Simon..........found the link you gave to Steph........I am up and running again!
Booster is installed on machine,will not open tells me to reinstall as piece (mfc120.dll ) is missing from programe please help
This is usually caused by a wrong or corrupted C++ Redistributables installation.
To correct the problem please proceed as follows:
-Start vcredist_2013_x86.exe located under C:\Program Files (x86)\F-Secure\F-Secure Booster\
-If you get the question "install or repair", please choose repair.
After this step it should work.