When posting to a mailing list, check your e-mail settings. Make sure you are only sending plain text to mailing lists. Others may not have the capability to read HTML coded messages and you want your message to be received and readable by as many people as possible. Many viruses are transmitted as attachments and as a result, most people wisely refrain from opening attachments on email from people they don't know. Check for typos.
Manners count online too.
Be sure to respect people's privacy and keep yourself and your family safe from those who might use information found online for fraudulent purposes. As you help others, they will be more eager to help you in return. No one wants to help someone who is constantly complaining or mean to others. By using common sense and following simple guidelines, you can benefit greatly from genealogical forums. They are a great place to make friends, find relatives, and information.