What version are you using? I remember that briefly in early v6 betas that was quickly fixed
If you want to TRY something first - go into the data directory and look for TBUSER.DEF and with the Bat closed, rename it.
- That will fix it and in that case you have to redo any customizations such as toolbars and keyboard shortcuts
- It WON'T fix it and in that case close the Bat and delete the newly created TBUSER.DEF and rename the old one back