I have a Macbook Pro, and I noticed upon upgrading to OS X Leopard, that the default message size for Mail.app messages was too small to read. Sure, you can add a button to your toolbar to increase font size on a per-message basis, but this gets old after the 1000th time. What to do about it?
Some Terminal magic will fix the problem. To increase the minimum font size for HTML messages, do the following:
- Open Terminal.app. One way - Spotlight search on “Terminal”, press Enter after selecting it from the Spotlight list.
- Type the following at the Terminal prompt and press Enter:
defaults write com.apple.mail MinimumHTMLFontSize 13
Now after a system restart your HTML messages will have a base font size of 13 points, which is much easier to read, and you can set the font size to a point size you are comfortable with.