How do I get past "waiting for any device" in adb when opening bootloader?

[Android Central Question]

I'm trying to open the bootloader on my Lenovo TB-8504F. After getting the tablet in fastboot, I type in "fastboot getvar all" in adb and it responds with "waiting for any device." Am I using the wrong command or something?

 

[belodion]

I don't know what to say, but by saying that, it will at least bump your post.