Open
Blue Iris Options, go to the
Clips and archiving tab.
A typical setup has 3 folders. Alerts, New, and Stored. You can edit their configuration by using the dropdown box "Select to edit".
Every folder has a size limit and an optional age limit, and you can specify what happens to files after one of the limits is reached (delete them or move them to a different folder). It sounds like you need to increase the limits so you make better use of your disk space.
Notice that a default setup stores clips in two different folders. First they spend some time in the
New folder, then they get moved to the
Stored folder. Then they get deleted from the
Stored folder. In my setup, I have modest limits for the size of the
New folder (48 GB and 2 weeks) and much larger limits for the
Stored folder (1000 GB).
The
Alerts folder typically holds only jpeg frames taken when motion is detected. Mine only has 22 files in it... evidently something is wrong and I can't even guess why. You can just ignore this one since it is of little value.