Why are backup logs being deleted?

My backup logs are being deleted? There were about 80-100 logs. Severeal times I have restored backup logs from past backups. These Logs normally stored in
C:\Documents and Settings\All Users\Application Data\Acronis\TrueImageHome\Logs.

The large majority are the "Warning - 'No Windows Libraries'" (becasuse this is XP and this is a known Acronis ERROR!). But my backup logs are being deleted, but the Warning logs are not deleted -
Where are the "Warning Logs" stored? Thank you. /Howard