error with font on Notepad

[thebluestar]

Once I deleted all my archive messages in Yahoo then I used the recovery software to recover all but I can not open them. They have extension file is DAT.
I tried to open it with Notepad but the font is not readable.
I do not know why!
Please help me to fix this!
Many thanks!

[cguan_77]

it seems a corrupted data...using a recovery software to get deleted data i don't think it can recover 100%..

[thebluestar]

Yeah, here I think they could be recovered 100%. I think the point is how it can be readable with notepad. I wonder about font.
My PC is not set up with any font software!

[Dukane]

Notepad is an excellent program for reading just plain text. It is not going to be able to read files which contain anything other than text. Are the chat logs in some kind of proprietary format? Are you sure these chat logs are plain text?

Before you deleted these files, with what program did you use to open them?