All emails have a different format (font, etc.) when opened in my computer.

After installing an Epson XP-241 printer all emails in outlook are shown with a diffent format that the one they originally were sent with. For example, the font and the size and the separation between de letters and the lines is not the default one.

If I send the email to another computer and you open it, it looks just fine.

This tells me that the problem is in the "format" that the email are displayed.  

Does anybody know, where to find the file that defines this, so that the emails display format can be brought back to "normal"?

Your help is appreciated.   Thanks in advance