By default, an index template displays the last N days worth of entries, where N is defined in your weblog configuration. For example, if you set the number of days displayed on the index to 7, Movable Type will, by default, display all entries from the last 7 days on all of your index templates. Note that 7 days means the last 7 consecutive days, not necessarily the last 7 days on which you posted an entry. So if you have posted on just 3 of the last 7 days, only the posts from those 3 days will be listed on your main indexes.
If you don’t post for a while you end up with “blank blog.” Fortunately this is easily preventable.
In your Main Index template, replace this:
Change the numeric value to however many posts you want on the main page. Save your changes and rebuild your Index templates. Blank blog will be vanquished forever.