Help ASUS Zenfone 5 LTE (A500KL) HS-USB Diagnostics 9006 Problem


Dear fellows,
My Zenfone 5 LTE has been working fine for the past 1 year plus until last week I installed a launcher (Samsung S Launcher) from Google Play Store.
It worked fine after installation, but after I restarted my phone, it turned off and could not turned on any more.
No matter what button or buttons combination I pressed, no response from the phone. Even if I plugged in the charger, no indicator at all.
When I plugged in to a PC, it was detected as Qualcomm HS-USB Diagnostics 9006 in Device Manager.
I have been searching on the web for solutions but to no available.
Appreciate if anybody can shed some lights on what I can do to rescue my phone.
Thanks a lot!