How to Read a Yahoo Messenger DAT Fileby Kefa Olang
Yahoo! Instant Messenger saves chat messages in a DAT file extension format in archives on your computer. DAT files are generic data files created by a specific application and can only be used by that application. They include text in binary formats. In order to view saved DAT text chats archived in Yahoo! Messenger you need to decode them. This simple process can be accomplished with an easy-to-use decoder program that allows you to view and read them in HTML format.
Download Yahoo Message Archive Decoder (see Resources below) and install it on your computer. Move to the next step to view archived .DAT files.
Launch your program after it has installed and select your Yahoo messenger user name in the "Select username" box.
Select "Private Messages" or "Conference Messages" in the "Select Type" box and press 'Next."
Select the user name of the person who you were chatting with when you saved the .DAT file.
Click "-> View" to open the whole saved .DAT file conversation.