received call from +65 3138 1701 at local time 18:48hrs on 30april2020.
the guy identify himself calling from windows total care center, technical department.
he said my computer just send windows an error message.

He then started off to say "I need to verify your computer id with you before proceeding."
he than instruct me to do the following:
- press windows logo key + R
- than type "cmd" and enter
- when see black screen, type "assoc" and enter. "you will see a long page of wordings and third line from the last is your computer serial number which I will verify with you."
- the third line from "assoc" cmd..
- he continued to instruct me type "eventvwr" and enter.
- he than asked to instruct to click on "custom views", and "administrative events".
- he asked how many number of events showing, which I replied over thousands. and he said "oh my god, so serious problem".
- by than google and found that there have been similar scams using similar that dated back as far as year 2012.

I hung up the phone after I told him that my computer has been working fine and if I encounter any serious problem I will call windows support directly.

this issue brought to my attention on how, where and when did they get information of my name and my mobile number and not sure what other information were in their database.