A light stopped working in a room. I checked both the fixture wires and switch wires for a current with a NCVT-1 voltage tester. Neither one shows a current. So I also checked the outlets in same room and my tester flashed red in both outlet slots. What does that mean?

The NCVT-1 stands for "Non Contact Votage Tester, with 1(one) probe"

What it means is that if the tester probe is on, it will sense the voltage just by touching the probe to one insulated conductor of a cable or sticking it into the short slot of a receptacle.

Not knowing which model you have, a whie or green light lets you know that the device is "ON" and working. The "RED" LED indicates the presence of voltage where the probe is touching.

For example, if you insert the tip of the probe into the small slot of a receptacle and you do not get a tone or a Red LED, then there uis no voltage present on that conductor. If it glows red and beeps the conductpr is hot.