Hello, Yes you can change and delete your logs. To delete a date range of logs, click FILE>>DELETE OLD LOGS, then you can chose how far back you would like to keep logs. To delete one log, click on the very left side of the grid and drag your mouse to the right side of the grid. To delete a remark on the log, click the bubble remark, then click the trash can on the bottom right of the grid to remove it. Hope this helps, if you need more help you can go to www.logbook.com and click on the CHAT NOW button on the right side to connect with a tech that can assist you.