If I do start /tab /pgm "%_cmdspec" Take Command hangs and I have to close it. Same if I do start /tab php C:\Mine\Progs\PriceCheck\Code\Test.php where php is an alias for "C:\Program Files%@if[%@max[%_wow64,%_x64] == 1, (x86)]\PHP\php.exe". Strangely, the command did just work once, but is now hanging again. A few times, I've gotten a tab, but with another window on top of the tab. If I try to move the covering window, it moves back to where it was when I release it. Clicking the tab's X makes the covering window go away. Both commands work fine without "/tab". TCC 12.10.66 Windows Vista [Version 6.0.6002]. Also tried TCC 12.10.66 x64 Windows 7 [Version 6.1.7601] with the same results.