Can you hold down the Ctrl-key when you click on the [...] button? If this works, then there is an association between the column data and an external editor that is not working.
After Ctrl-clicking on the column, can you go to the "External" tab page and check if the "Execute automatically next time" option is enabled? If it is enabled, disable it and try again.
If this does not apply, can you go to Preferences > User Interface / Options and press the "DSA Dialogs" button? Check if there is a line with Edit. or View. for the data type of the column. If such a line exists, delete the line and try again.