Using Office XP (Outlook 2002) but hopefully settings are the same ..
In Outlook, Tools, Email Accounts, Change ... there should be two addresses - delete the unwanted one from each PC
HTH - please post back results or problems
Huawei P10 review
1995-2015: How technology has changed the world in 20 years
An overview: What leading creative agencies are doing to improve diversity
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.