Let's assume he has the original settings -or not- how and where can I read all previous chats? Is there a logg somewhere on the PC? Or anything that stores all conversations?
It should be in My Documents under like saved messages or chat logs. On my computer it used to have each individual chat log with another email address and you can look at all of the conversations over time. I'm guessing you're investigating your boyfriend? Don't feel bad if that's it- that's totally what I did too! Good luck and if that's the case and he's cheating, dump his lame ass!