As the old saying goes, "One man's spam is another man's hot LinkedIn prospect." That's why you never want to post your LinkedIn cold call inmail to a group on LinkedIn (even if you get a friendly response).

It can come back to haunt you in an instant if someone in the group you randomly contacted decides to report you. How many inmails can you send a month? That depends on how many groups you have joined. You can send up to 100 inmails to each group, so if you have 5 groups, that's 500 inmails a month, so 500 / 100 = 5.

You might be a little confused right now. We're talking about InMails, not emails, but don't worry, we're not being redundant. InMails are a feature of LinkedIn, and they are meant to be used for professional communication.

They are sent by members to other members and don't show up in your sent messages or in your email inbox. You can send 10 InMails a month—but don't worry if you go over that number because you can send as many InMails as you like without getting a warning message as long as you wait a day between each one.