Norton 360 Premier stops opening every week

Hi:

First time having to use forum for a problem. Just had to reinstall 360 for fourth time due to inability to open the program. Program stopped opening intermittently starting three weeks ago. Main problems along with this or occurring before program stopped opening were:

1) Whenever turning computer on or waking up, CPU activity goes wild like its doing a full system scan even though I have scheduled to do manually. Effects on running other programs is minimal but 360 becomes really slow in responding. Even keeping 360 open all the time does not prevent.

2) Three of four times has become unresponsive Wed/Thurs (Windows updates causing?).

 

360 version is 22.9.0.71

Windows is version 7 with service pack 1 (really old computer, but before this everything worked great so didn't want to change anything until had to).

Two free malware/anti-virus programs have found nothing and 360 has found nothing every re-installation.