Bruce, to possibly fix this on your system with the Design Sheet open I would open the View Organizer wizard from the View menu and select the Design Sheet as the file and Procedures. Double click the .Initialize procedure and when this opens go to line 40 with the
openform statement and remove the “maximizable”,“no” option from that line of code. Save the file, close it and then reopen it. Select the ToolBar window and now the Show Tab Bar item should be active. Try toggling it on/off and see if the tabs disappear from the ToolBar window. If they are removed you can save once again and hopefully your problem will be over. Now when the ToolBar is reopened it will not have the problematic maximizable option executed.