I have the same problem it takes 2 to 5 mins for my word to be useable, have you tried contacting Symatec it's hopeless.
It also bins all my e-mails even on the lowest setting have had to disable internet security.
Huawei P10 review
1995-2015: How technology has changed the world in 20 years
How VR is being used to simulate space
New iPad, iPhone SE & Red iPhone 7 on sale now
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.