Timeout issues are one of the most common questions raised in data access development.
To resolve this issue, the common troubleshooting step is increase the php timeout value to a larger value.
If you can't change the timeout value you can:
- export the articles without images. You can export the images later via ftp.
- export data in bulk. Select 500 articles at a time
http://yourwebsite/administrator/index.php?option=com_content&limit=500&limitstart=1
http://yourwebsite/administrator/index.php?option=com_content&limit=500&limitstart=501
http://yourwebsite/administrator/index.php?option=com_content&limit=500&limitstart=1001
and so on...
With System - Limit 500 plugin you can select 500 items at a time from pagination.