My replacement Toshiba Satelitte with Windows 8.1 sometimes displays weird behavior when signing on, especially if it hasn't been used for over 24 hours and is run off the battery. Sometimes the blue log-on screen circles a long time without bringing up the Windows 8 desktop, and then says "Group ID" missing. If I click one more time, it comes up. Or it may give a black screen, with the circle spinning, and shows the command prompt a few times, too quickly for me to see the message, before it finally comes up.
The problem is not reproducible, and doesn't seem to happen unless considerable time passed since last use. Some posts online suggest a CMOS issue.
I will need to depend on this laptop when traveling, and sometimes there would be periods when it isn't used much. It performed perfectly in New York the last weekend of October, but was used often.
The best link I can find on the problem is at Tom's Hardware, link. There is also a link on clearing CMOS here. It sounds logical from symptom pattern that it could be a CMOS issue.
I sometimes had the "Group-ID" problem on the older Toshiba, that broke in August.
Here's another oddity: I left the Cannon Power Shot in a USB drive on my HP Envy longer than I needed it, and suddenly a SanDisk ad pop-up occurred.