Page 925 - Windows 10 May 2019 Update The Missing Manual: The Book That Should Have Been in the Box

Figure 18-11. To sign in while someone else is signed in, just press the magic keystroke (to open
the Start menu), and then click the current person’s account photo. Boom: There’s the list of people
with accounts on this machine, including you.

Robin can now click the Robin button to sign in normally and do a little
work or look something up. When Robin signs out, the Accounts screen

comes back once again, at which point you can sign back in. Without
having to wait more than a couple of seconds, you find yourself exactly
where you began, with all your programs and documents still open and

running—an enormous time-saver.

Authenticate Yourself: User Account Control

Work in Windows long enough, and you’ll encounter the dialog box shown
in Figure 18-12 at top. It appears anytime you install a new program or try

to change an important setting on your PC. (Throughout Windows, a
colorful icon next to a button or link indicates a change that will produce

this message box.)

Clearly, Microsoft chose the name User Account Control (UAC) to put a
positive spin on a fairly intrusive security feature; calling it the IYW

(Interrupt Your Work) box probably wouldn’t have sounded like so much
fun.

Why do these boxes pop up? In the olden days, nasties like spyware and

viruses could install themselves invisibly, behind your back. That’s because
Windows ran in Administrative mode all the time, meaning it left the door
open for anyone and anything to make important changes to your PC.

Unfortunately, that included viruses.

Windows 10, on the other hand, runs in standard mode all the time.
Whenever somebody or some program wants to make a big change to your

system—something that ought to have the permission of an administrator
(“The Types of Accounts”)—the UAC box alerts you. If you click
Continue, Windows elevates (opens) the program’s permissions settings just

long enough to make the change.