In Windows 7, I use the "Auto-hide the task bar" feature.
Usually, it works fine: As soon as the pointer touches the screen bottom, the task bar pops up.
However sometimes, it refuses to rise. Pressing the "Windows" key (or Ctrl-ESC) makes the start menu appear, forcing the task bar from hinding as well. Once I've done this, the task-bar auto-rises again. This is annoying, it interrupts flow. Has anyone else noticed this? How do I avoid this?
Searching for "Windows 7 task bar auto-raise" shows that at least one other person experienced this problem:
http://answers.microsoft.com/en-us/windows/forum/windows_7-desktop/how-can-i-fix-the-taskbars-auto-hide/8cdf6369-7354-4d29-9249-b7096ed0e28b?msgId=6dac3361-9d0f-4a9e-8642-b91a72826ba4
To answer the question posed by the "helpful" support engineer on the above page, of course I am running some apps when this happens, usually Explorer, Firefox, Eclipse, Cygwin/X, Xterm, Emacs, Notes, VPN client, Firewall.
If my memory serves correctly, I have seen this behavior on earlier versions of Windows as well, XP at least.
To reproduce this behavior, I tried switching between apps, and bringing apps to open other windows. I am unable to reproduce this behavior so far. So far, it appears to happen out of the blue, sometimes multiple times a day.
Looks like a bug to me. The task bar should raise no matter what.