That might be due to people getting virus alerts from the site. Maybe swap to a different blog hosting site?
When posting an article you're allowed to post the link, but only as long as the article is also posted along with it. Rather than forcing people to click the link to read it.
Once the virus issue is eliminated members ARE allowed to link to their own site/blogs etc in their sig. Spamming the link across the forum (not saying you are, btw) however, is not allowed.