The track list is the area on the left of the tracks. Two things. Firstly, move your mouse cursor over the line between the tracks and the track list, until you get a double arrow. Left click and drag to the right. Then move the cursor to the line underneath the audio track in the track list, left click and drag down.
Vegas has many features you can modify, to make your life easier. You clearly need to invest some time reading the manual, or help screens. Sorry to be so blunt, but if your best friend can't tell you, who can?
Hello my friend, no success. I expanded the cell to the maximum extent practical and there were no hidden icons! Curious, if you right click for your Set Default Properties, does your Audio Default Properties have an option to click for "Arm Record"? Mine doesn't.
There are several reasons why the Arm for Record button wouldn't appear in the track header:
1) The Track Headers are too small and need to be expanded (as you suggested)
or
2) There is no Audio Device Type selected or it is not detecting a sound card. Open your Windows Sounds and Audio control panel and select the proper recording device (mic, line in, etc.). Now return to Vegas and select the corresponding Audio Device type from Options>Preferences>Audio Device. If it's your PC's onboard sound card, then it's Microsoft Sound Mapper. If it's a USB or Firewire device, then it's either Windows Classic Wave Driver or the driver specific to that device.
so what happened? Vegas didn't detect the card or it was setup as a wrong one? Strange that would happen, i've never seen that happen before (but I have changed the settings, don't remember if I had issues though).