9. People complain my emails have weird characters and spaces in them
Outlook 2007 uses Microsoft Word as its mail editor. Even if you don't have Word installed on your system, Outlook uses a Word.dll, and so Word is what you get when you compose mail. Because of that, when you type an apostrophe, quotation mark or some other special characters, they may show up in other people's email as blank spaces or oddball characters.
The problems are caused by Word's use of so-called smart quotes, which from some points of view aren't so smart. They're not plain-text characters, and so other email readers may interpret them oddly, particularly if the email reader uses plain text instead of HTML.
To fix the problem most easily, in Outlook select 'Tools' and then 'Options' followed by 'Mail Format', and from the drop-down box in the Message format area, choose Plain text and click OK. From now on, Outlook won't use smart quotes. However, it also won't use HTML, either, so you won't be able to use fonts, colors and so on.
If you'd prefer to use HTML text for most messages but use plain text only for some, when you create an email message, select Options from the ribbon at the top of Outlook, and click Plain Text. That way, only that message will be created using plain text; all others will still use HTML.
There is a way to use HTML for your messages and turn off smart quotes at the same time. Select 'Tools' and then 'Options'. Click the 'Mail Format' tab, and click the 'Editor Options' button. Click 'Proofing', select 'AutoCorrect Options', and then click the 'AutoFormat as You Type' tab. Uncheck the boxes next to 'Straight quotes with smart quotes', 'Ordinals (1st) with superscript', and 'Hypens with dash'. Click OK, and keep clicking OK until the dialog boxes go away. You'll be able to compose HTML mail from now on, but without the oddball characters.