Error message upon saving article

Hi Ronny,

Since this occurs only in a specific article I think that this might have a corrupted image.
Here are some things you need to check:

1. Remove the intro and full images and try again.
2. Check for any custom fields with images.
3. Check for any invalid images in your article content.

Finally you need to check that PHP GD is enabled in your server. You can find this information in Joomla administration area under "System" -> "System Information" -> "PHP Infomarmation.
PHP GD is required for processing images.

If none of the above helps, try to disable for a while Econa and Showtime plugins and see if you will get the message. There is always a chance that this message comes from a different extension.

Regards