This problem usually relates to a null value in a "bit" field. The Edit Dialog needs the database value to be non null.

To solve the problem make sure that a default (non-null) value is assigned at the database level and ensure that all current records have a non-null value assigned.

http://support.microsoft.com/default.aspx?scid=kb;en-us;295626

Firefox 2 made some changes to the way dialog windows behave. In order to allow DbNetGrid to bring these dialog windows to the front you need to make a change to the options.

1. Select Tools --> Options --> Content
2. Click on the Advanced button
2. Check the option Raise or Lower Windows