After I enable the sandbox option,
I have 2 same account when I boot my PC, and this cause I can't login normally, 

it will always occur alarm (login the sandbox account, and poped wrong password message), to force me login the right account manually.

I tried this post and success remove the itch user,

but the itch sandbox account still appears and try to login when I boot my PC.

I've try uninstall the itch app and delete the itch user account in C:/Users too, but it still not work.

It is really a nightmare when I boot my PC now, how do I remove the sandbox account exactly? Thank you ;(