Yes, you can shut down or reboot your computer. When the downloaded executable starts, a dialog box immediately appears requesting that you close all open programs. Even though the executable has started, the firmware upgrade doesn't start until you click on this box affirming that you have closed all open programs. In my case, the instance I clicked on OK, my PC rebooted and the bios update began.
We're seeing two situations happen:
1) The dialog box never appears, meaning that Support Assistant isn't starting the update executable.
2) The dialog box appears but behind the Support Assistant window, meaning you can't see it so you don't know that the upgrade won't start until you click on OK to initiate the process.
In either case, the actual update hasn't begun, so you can shut down or reboot your PC.
Mine did the same thing. As it turned out, a dialog box requesting my input had appeared BEHIND the Support Assistant window, so it wasn't visible. It appeared after I minimized the Support Assistant window, and had been visible on the taskbar, which I had neglected to look at. Once you click on the appropriate button on the dialog box your firmware will be updated - your computer will reboot, and you can watch the progress as it goes through several steps in the upgrade process.
Better stated: when the firmware download finishes, Support Assistant appears to freeze. In fact, a dialog box has appeared BEHIND Support Assistant and out of your view requesting your permission to reboot your computer to update the firmware. If you don't notice this dialog box and reboot the computer, yourself, it reboots normally - your firmware is NOT updated, nor is your computer harmed. If you use the dialog box to reboot your computer, then the firmware is updated during the reboot process - you are shown the progress of the update as it happens.
I have had the same problem with the Alienware system bios not updating.
In my case there has never been any window hiding behind the SupportAssist window
waiting for any response from me to continue.
I had the same problem, and I ended up using the manual updater.
What I would suggest is close the auto updater when it hangs, not reboot, and run the manual bios updater.
I think that's a better solution than rebooting when the auto updater might or might not have completed the flashing process.
For the latest update (1.0.4), I googled "Alienware Aurora R11 System BIOS" with the quotes. I then clicked on the matching Dell link. It brought me to a page for the previous bios - 1.0.3. On the page, there's a section that says, "Get the latest driver." I clicked on "Enter Details." A popup appeared that requested my Service Tag or Model. After providing the information, it took me to the correct page for bios 1.0.4. I manually downloaded the 1.0.4 install executable and then executed the downloaded file. It requested that I close all programs, which I did. It then rebooted my PC and installed the updated firmware with no issues.
The behavior this time was different than with 1.0.3. With 1.0.3 I had a dialog box open behind the Support Assistant window, so it was out of sight. This time, as some previous posts stated, no such dialog box appeared. So I manually download the file from the Dell website and executed it, myself.
Another thread I viewed strongly suggested that we don't use Support Assistant for firmware updates, stating that Support Assistant had in several cases messed up the firmware upgrade and made the computer unusable. My first attempt at downloading the upgrade executable worked without a hitch. If anyone has a less positive experience, please let us know.