Actually, if your members are not using post.asp to make their blog entries, you could simply make the blog forum private.
Otherwise, try this. Don't forget to backup active.asp first, just in case
Find the following beggining on line 194 and add the code in green, where x is the id of the forum you use for your blogs:allowSql = "SELECT FORUM_ID, F_PRIVATEFORUMS, F_PASSWORD_NEW"
allowSql = allowSql & " FROM " & strTablePrefix & "FORUM"
allowSql = allowSql & " WHERE F_TYPE = 0 AND FORUM_ID<>x"
allowSql = allowSql & " ORDER BY FORUM_ID"
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