USB debugging - No device found after chrome update After attempting to begin remote(usb) debugging I finally had my phone recognised via the chrome/inspect page. At which point I was told I must update to chrome 39.0 Beta to access debugging. 

After doing so the phone is no longer recognised.
Xperia Z(C6603)- Android 4.4. - Chrome was on 38. Has been updated to 39.0.2171.62 (Official Build) beta-m

I'm new to all this so any help/suggestions would be amazing!

Thanks!

I have since uninstalled chrome to remove the beta and re downloaded with Version 39.0.2171.65 m and still no devices found.
I had the same issue. Got it working again using Chrome Canary:

https://www.google.com/chrome/browser/canary.html

Imho it's the DEV-Release - more Beta than Beta but finally i can debug my Xperia Z again.