Hi,
Do you have components/com_grid and administrator/components/com_grid folders on your server?
Are there any files in those folders?
Is Tools JX listed among other extensions in Extensions > Extension Manager > Manage?
I strongly recommend updating to the latest version of Joomla. Not just because of the compatibility with our extensions, but also because of the safety reasons. The procedure is very simple. Just go to Extension Manager > Update and follow from there.
After updating Joomla I would recommend reinstalling Table JX.
First uninstall it from Extension Manager > Manage.
Then make sure everything is deleted on the server ( components/com_grid and administrator/components/com_grid).
After that delete database tables: _grids _grid_conn and _grid_columns. Then try installing it again.
Regards,
