Version 2.8.8.0 comes with new in-program debugging information.
If you ever have problems with any "Bulk Send" feature, you can copy ALL of the text in the Debug Information section and email it to us. This will help us identify the problem or where Tube Toolbox is getting hung up. On the Sending Status screen, click on the "Options / Debug" Tab and copy all of the text from the Textbox, then email it to us.