Avoid these common mistakes if you want your emails to look professional...
1) Who are you talking to?
Are you really on first name terms with the company lawyer? You need to be addressing people correctly by email, just as you would in person. As a rule always make the first contact using a title and last name (eg. Mr Smith). If they initiate first name terms, either by using yours or by signing with theirs, it is usually okay to respond with theirs. Always err on the side of caution, there are some uptight emailers out there, and familiarity breeds contempt.
2) Choose a font with caution
I know there are hundreds upon thousands of fonts out there, but maybe your company email isn't the place to try them out. They may be boring, but you really can't go wrong with Arial or Times New Roman. Comic Sands is only acceptable in business communications if that business is a six-year-old's lemonade stand. Oh, and black is the new black,,,no one will take you seriously if you're typing in Barbie Pink.
3) CAPITAL LETTERS and Exclamation Points!!!
WHY ARE YOU SHOUTING?! There is really no need to use capital letters for emphasis on a well written email, it should be implicit. Using an exclamation mark to finish every sentence makes you the email equivalent of an excitable puppy. Just calm down. If you really must use them, carefully select one sentence where it is most appropriate.
It is not 1999, this is not MSN messenger, there is absolutely no excuse for sending a professional email peppered with smiley faces. You may think you're coming across as friendly and approachable but in reality you're flushing your professional credibility down the toilet. You are not a child, use your words.
5) Urgent! Urgent! Urgent!
Before you mark that message as high priority and hit send, take a moment to consider whether it really is urgent. Using this function too often has a boy-who-cried-wolf effect; if you marked a cute-cat-circular as urgent, when mail really is important no one will take you seriously.