Thats the problem. 1.3.11 is incompatible with the automatic upgrade functionality in WordPress 3.0, they made changes to the WordPress core that required changes to Gravity Forms.
We released 1.3.12 which fixed this issue before WordPress 3.0 was released. But if you upgraded to WordPress 3.0 before updating Gravity Forms, automatic upgrade won't work.
You will have to manually download Gravity Forms 1.4 from the Downloads page and install it via FTP. You will need to delete the existing Gravity Forms files and folder (plugins/gravityforms) and then upload the new plugin folder from the 1.4 zipfile.
By simply deleting the files you won't lose any data. Then upload the new files and make sure it is still activated and you should be good.
Posted 9 years ago on Friday September 10, 2010 | Permalink