Hi, the problem started a few weeks ago when my mother (91) tried to log on to her gmail account. Several tries but all that can up was my sister-in-laws account. I assumed that whilst visiting my s-in-law had checked her email on mother's computer and switched off without logging-off. Re establishing auto entry two her own account seemed to fix the problem. However, my s-in-law told me that today when she logged off from her own gmail, on her own computer (100 miles away) my mothers account was open on her (s-in-law's) computer. she could open and could have read any of those emails.
Mother has 'Team viewer' installed so that I can help her but s-in-law's computer is in no way linked.
Both use XP, and both have gmail accounts.
My question then is "How can someone's email account appear on another persons computer?" and "How can it be prevented?" Hopefully given the answer to the 1st I can work out the 2nd! But all ideas are welcome.