How to view old skype conversations?

I use skype and im trying to look at old conversations i have with a specific user. I want to go back 2 years or so but it seem to only go back 14 months. Is there a way i can view my old conversations all the way back there or even before that? Its an important chat because it involves some financial information i need.

I read online that you go to run and type in %appdata%/skype



Then find your username for skype and click on itThen find the main.db folder.



I do see something called main and it seem to be big file.


It say its a db file and editing or modifying them could damage your system.


When i click it, it shows programs i could open with it such as


adobe
notepad
wordpad

etc


Can someone tell me what im suppose to do? And is it safe since i got that message?