I just opened the forums for my web hosting company, but obviously linking empty forums is a horrible idea. Personally I don't know anyone that would spend time posting threads there for my companies benefit, does anyone have any ideas as to what I can do?

Well as the forum moderator, you could do one of the follow:
-create sticky posts in all categories
-create open ended discussions for people to contribute to
-create fake accounts and start conversations that way

I think some forums actually pay people to make initial posts, but that may not be the best solution.

I honestly would not recommend making fake names, and making fake posts and threads, that is just the sign of a failing forum before it starts.

Here are some other ideas:

- Pay for a banner on some successful forums
- (Agree) Add dofollow
- Email SEO companies with the address if it is a dofollow forum (you will gets posts then, no matter what the industry)
- Competitions - (first 3 people to make 150 posts get $40 each)
- Top 5 people with the most posts get a sitewide link
- Be an active member in multiple forums related to yours

These are all ways to drive more people to your forum, and to get them to contribute.

Hope it helps.

Another way would be to optimise the website to show up highly for related keywords.

I agree with above all he answers, it will help me too,,..
thanks..