I searched but couldnt find any problem like this, so that any solution. My members sometimes login as another member. They can change their account, they can ask as another member.
to explain clearly, for example I registered here as civil.engineer; I posted questions, some answers etc. after 1 week i try to login but it doesnt ask me the username or password. it automatilacally log me in as another member ( for example Jackson) and i can continue as Jackson on the website and can ask questions, answer, also can change Jackson's all account informations include his password.
Thats a big problem, what can be the reason ?
Edit : My hosting company upgraded php from 5.3 to 5.4. This problem occured after this. I transfered my site to another server which php 5.3 and reloaded my backup. After all, I thought it is ok, the problem is solved. But it is still contiuning. Becaue old logins as another user, probably has the cookies and still continue. Yesterday my friend called me and said I login as admin. It was my friend but if is not, he could blow up my q2a :)
What can I do ? May be make logout all users will solve this problem but how can I do ?
I believe the solution on mysql database but I dont know where to check.