If you open TntMPD and get the error, "Internal Error: Can not find CountryID -2" try this:

1.  Under the "Tools" menu, click on "Options". 

2.  Under the "International" tab, select the Default and Mailing From countries. 

3.  Click "OK" and close TntMPD. 

Next time you open TntMPD it should be back to normal.