My inner geek is exhausted! I have followed instructions to delete files from an almost-full SD card in my sensorstation using the web interface, Filezilla, and command prompt, and in every case (despite success messages, in some cases), the files remain on the card, leaving no space for new data. I finally got Filezilla to recognize the sensorstation by using pi as the user and raspberry as the password, but despite changing the permissions so that anyone should be able to drwe the files, couldn't delete them. When I changed the user/password to root/root, the directories completely disappeared.
In command-prompt, root was not recognized as the password for user root. It may be possible that the password was changed before I got this sensorstation. It had previously been tested and even deployed briefly by BirdsCanada. Is there any way for me to delete files and free up some space?